[CenturionDk]

Hi All,
 
I'm driving myself crazy the last few days reading reviews and other links on the forums about each of these IEMS but I'm just getting myself more turned around.
 
I had a set of M1's that I liked a lot but had an unfortunate run in with the washing machine, so I'm currently using my backup set which is Sennheiser 475.  I'm not a big fan of these Sennheisers so I'm in a hurry to replace my M1's. 
 
I'm looking for something with good sound isolation, I listen mostly at work, at the gym, or while remodeling my house.  I like bass at times but I'm not the type that wants it all the time because it can end up giving me a headache. Also I'm generally listening to music on my razr smartphone (root with Beats drivers).
 
How powerful is the base on the FX3X?  Headache inducing?
 
The M5's are described as "allowing you to hear each instrument" - Does that mean they are the cleanest of the 3 for vocals? Does it also mean you get less listening fatigue from them?
 
The M2's have the highest price tag, are they the best all around? 
 
I'm open to getting 1 set for the gym (probably the FX3X?) and another set for work, but I don't want to buy all 3!
 
Secondly, is there any benifit to buying a FIIO amp with the headphones?  I'm not sure if it's a waste on razr smart phone streaming pandora...
 
Guidance would be appreciated!

 

[NA Blur]

When you say M1 what brand are you referring?
 
If it is Brainwavz then the M2 is what I use at work and around the house.  I really enjoy them as they have an up-front midrange and a decent amount of bass for a non-bass head like myself.  I added some Comply T-400 foam tips to achieve a better seal and the sound improved in addition to being able to isolate much better over the stock tips.  The T-400 foam tips also add quite a bit of comfort as it gives a bit more space between the IEM body and the outer ear which is the reason I make them a necessary purchase.
 
I do not use an amp with my M2 unless I am at my desk and I only get about a 5-10% increase in sound quality because of it.  My iPod touch drives them just fine.

 

[ZARIM]

If you like deep punchy bass and over all very crisp clear soundquality then you will like JVC FX3X and they canbe use for Gyme and outdoor. Sony XB90EX are another bass but detailed IEMs and they both built sturdy.

 

[CenturionDk]

Sorry, by M1 I did mean the brainwavz. 
 
Thanks for the input. I had been leaning towards the M5 but had concerns that it wouldn't be what I was looking for.
 
I'm thinking about getting both the M2 for general use and the FX3X for the gym.... I just don't know if I want to shell out 100 bucks on two IEMs. So I might end up just getting the M2's. 
 
Thanks for the help and if anyone else wants to chime in I'll check back a couple times before I make a decision