Etys require a very deep fit. Sounds like you didn't achieve that.

You must have something wrong with the fitment, Ety's are supposed to go deep, real deep...

All foam tips fall apart with time so why would you put that as a con? And no, I'd take the MC5 over the bland boomy cx300. To put it bluntly, if the MC5 feel comfortable in your ears then there's a problem. From my experience only the mushroom tips are capable of sounding right and feeling perfectly comfortable. Many people dislike ety for that reason.

I would know if they were not fitting correctly. I put them in deep (that's why I said the isolation was excellent) These are awful sounding. Plain and simple.
Also, my analysis of the sound matches what others have said for the most part.
As for all foam tips coming apart, I should have said I would have liked rubber tips of similar shape (non tri-flange). But having foam tips that fall apart so easy is a con, whether or not other tips have the same problem.
Headfi is all about denial: if headphones don't sound good, then they need 100 hours of burn-in, or they need a better amp, or they're not being fit correctly. Well, I listened to that BS when I decided on these and made a huge mistake. These sound like crap.

Upgrade to hf5 and be happy forever

from what I've read the HF5 has less bass and ever more thin sound.

It's anything but lifeless though. Nice and fast and articulate and makes drums actually sound like drums >_>

Ohhhhh.... Looks like someone bought Studio Monitors instead of casual earphones. And by going in deep it means they have to go an almost as much as a cotton earbud, and if one tip doesn't work try another. If they still don't sound good it means you weren't looking for studio monitors in the first place. Same thing happened to me with a 280 Pro.

That's all we need..more 1/10 reviews from people because they don't like it's sound signature. Is there any headphone/IEM that doesn't get a 1/10 from you?

Everyone I just realised we can't take this guys reviews seriously He has absolutely no ear. He's a fan of Dr. Dre's which are good for nothing but blowing your head in (Ala Skull Candy). Better check other reviews.

More headfi denial.
Dhruv, you rely on false ad hominem accusations. Not everyone who disagrees with you is a "fan of Dr. Dre's". I own a pair of hd600s you stupid ****. I don't even like Dr. Dre's music, let alone his bloated overpriced headphones.
Also, IEMs aren't "Studio Monitors". They are used on stage, not in the studio. I was completely aware that they are advertised as having a neutral sound, and I even mentioned that I like analytical sound signatures, as long as they are detailed (which these aren't).
Tefloon, you also make a stupid remark. What, I can't use the same pair of inexpensive IEMs for comparison?
tdockweiler, I gave the hd600s a nice review. Also, I would rate the cx300s higher than these pieces of overpriced garbage. I believe reviewing the sound signature sort of the point...
Here are some other people who had similar impressions as I did:
http://www.pocket-lint.com/review/4868/etymotic-mc5-headphones-earphones-review
http://www.inearmatters.net/2010/10/review-etymotic-mc5.html
http://www.head-fi.org/t/547458/not-impressed-with-etymotic-mc5
http://www.anythingbutipod.com/forum/showthread.php?t=59743
http://www.advancedheadphones.co.uk/blog/headphones/192/

Eisenhower HD 600s have been noted for bass alot of times so just realise that you are a bass happy person, if something doesn't have alot of bass it doesn't mean it's bad, it just means you didn't like it because there is no bass. I have seen the same review of your for 280 pro, and I happen to own the 280 pro, though I don't like it for casual listening, it is quite good. I would really love to hear your opinion on the Audi-Technica ATH-M50 headphones, get them and tell me what you think. Then I'll decide whether you're really credible enough.

"Lack of bass" and "enough bass" are very subjective descriptions. the MC5 does have bass, it is light, tight and accurate. nothing boomy or loose.

Dhruv, I have never heard ANYONE describe the hd600s as a bass heavy headphone. It has a balanced amount of bass, on par with other expensive headphones.
If a pair of headphones lack enough bass to make music sound bad, they are bad headphones. This is true with both the 280 pro's and the Ety mc5's. That doesn't qualify them as "studio" headphones, at all.
I have nothing to prove man. I don't care whether or not you think I'm "credible". I think your full of crap, so how about you prove yourself first?

Eisenhower You prove yourself first cuz no matter how bad you think they are they definitely aren't 1/10 star headphones. I'll give you 1/10 star headphones(actually skull candy's prettty much win in the 1/10 star segment) So why don't you give an actual legitimate review after using some studio headphones for mixing for bands and electronic artists and then come back.

The main thing I have a problem with is how shrill and disgruntled you're coming across. If you don't like it, by all means, sell it and pan it. I've never personally heard the MC5 -- it could very well be all the things that you say, but you still could have communicated them in a far better manner. Your review makes you sound Angry and Entitled, which isn't helpful to anyone. If these kind of rants are the purpose of the review section, it really shouldn't exist at all :/
The reason that the low-end IEM comparison isn't helpful and hurts your credibility is that they are generic/bassy consumer IEMs -- that tells me or anyone else who's reading you're not interested in the accuracy of the thing at all. And when it's applied to multiple headphones, that just makes the suspicion that you're putting them on, listening for 10 minutes, and writing a disgruntled review of the sound sig even stronger.
Another bone to pick while I'm at it: IEMs can and do have soundstage. On my hf5s ad even my RE0s, I can hear the positions of instruments relative to each other and the center of my head. >_>

Tefloon, my review sounded shrill because these are very bad headphones that had a large amount of hype behind them. No one complains when Beats or Skullcandy headphones get this type of lambasting, and yet these headphones are as poor as them. My review wasn't BS, I discussed each part of the frequency individually. If my colorful commentary offended you (do you work for Ety or something?), then stop reading it.
When Ety advertises these as being the "Best-in-class" or that they have an "85%+ accuracy score", and sell me a poor sounding IEM, I am allowed to criticize.
Why would I compare these to much nicer headphones, when they aren't even as good as cheap ones? More people own cx300s than say meelectronics m9's (which I owned and broke), so it makes sense to use them as a litmus test. Does it mean that I'm not interested in accuracy? No, it means that I found the cx300s to be more enjoyable, regardless of accuracy. I listen to music because I enjoy it, after all. I explained this in the very beginning: "They manage to suck all life and energy out of any track I listen to. I actually enjoy an analytical and neutral sound signature. These however don't have the detail or sparkle to make up for it's lame frequency response."
Also, you apparently don't understand the difference between stereo sound and a sound stage. Can your IEMs make music sound like its coming from in front of you, and not "in the center of your head"? I don't think that's possible without using angled drivers ala speakers (like my hd600 has).

Well, if you want to scream at Head-fi about how bad your headphones are and how everyone is trying to trick you into buying terrible headphones, I suppose it can't do anything worse than annoy a few people... Never said you weren't allowed to criticize them -- I just see more to be gained by doing so in an objective manner.

I also don't really see how this is very similar to Beats/Bose -- Etymotic doesn't sell headphones on the strength of their PR machine.

Um, writing a negative review of a product that I purchased isn't "screaming at headfi".