These headphones are a perennial source of frustration for me. They sound fantastic for closed headphones at their price. I'm a big fan of neutral and detailed cans with a fairly flat sound signature, and these definitely deliver. Highs are crisp without being at all harsh, mids are clear and detailed, bass is well balanced and controlled. Sound wise, these are probably my favourite closed headphones of the ones I've owned/trailed (DT250, DT770, M50x).

Build wise, these are my least favourite. They are made out of brittle plastic, which doesn't seem very durable. The plastic is also quite noisy, especially around the joints between the cups and headband, and the headphones creak if you move your head much at all. I've had mine for a couple of years and used them pretty heavily, and the creaking has gotten worse over time. It is particularly audible when listening at low volumes. The headband presses down on the top of your scalp and becomes uncomfortable after a while. The headband material also degrades with time, and there doesn't seem to be an easy way to replace it.

I think these could be truly excellent cans if Shure had done a better job with build quality.

I've been using one of these in the office for a while now with various headphones and IEMs. It's kinda difficult to assess something like this because it costs under $100 and comparing it to other equipment I own, some of which is several times the price, seems unfair.

First of all the build. It seems very well made for the price. Nice solid metal chassis. A good smooth volume knob and the jacks all seem secure. It's also very light and very small, which I like. Perfect for carrying around with a netbook or something.

But the sound. This is the big negative. Going from the E7 to E10 as a DAC/amp combo I immediately noticed the E10 was less muddy sounding, with less emphasis on the bass and more prominent, smoother treble. It seems to be trying to achieve a more hi-end, balanced sound. This should be a good thing, but unfortunately it just lacks the detail. What you end up with is something that betrays its own lack of refinement, there is a kind of fuzziness where the details should be. Using the line out and a different portable amp (a JDS labs cmoybb) improves things a fair bit, but ultimately the DAC is just as much of a problem. Like I said, it's hard to assess this because it is only $100, but even compared to a $30-$40 soundcard like the Xonar DS, the E10 comes second best. I suppose if portability is the priority, then it is worth it. But for a desktop computer, soundcards are going to offer far better bang for buck.

Using it with pricier headphones (like the T70, RS-1 for example) seems to me like a bit of a waste when I've come from hearing them on better gear (for example an STX). I really notice where the detail and punch is missing. I'd probably say to someone who has invested more than ~$250 in a pair of headphones not to bother using the E10 with them. It's certainly enough of a bottleneck to warrant a better source.

Also, the amp was certainly loud, but not quite up to powering more demanding headphones. For example, it drove all my IEMs with considerable ease as well as my AD900s. But even reasonably efficient headphones like my 80ohm DT250 and T70 feel flat and lack dynamism. Now it could just be the lack of sound resolution making them seem like that, but I don't think so because it is not something I noticed with the more efficient gear. The JDS labs cmoy just walks all over the the E10 in this respect, especially if you pump the power up north of 15v.

Having said that, I don't mind the E10. It's certainly well made and would serve someone well as a durable and portable little device that improves on onboard or laptop sound. In my office, for example, I don't have the luxury of installing a soundcard so I'm happily using it until I get something better. It's also fantastically easy to use, IMO much improved in this respect over the fiddly buttons on the E7.
If you can use an internal soundcard though, there's really no competition: For my money, Asus and Auzentech's offerings are by far the best bang-for buck audio gear in the sub $100 category.

So what this device is really great for is situations where you need a small, cheap, portable amp that can offer a decent upgrade from stock computer sound. Like if you wanted something to carry around with your laptop to listen to your IEMs through. Or if you are in an office and and something discrete and decent for some efficient headphones. In this respect the E10 excels. It's certainly better than any smartphone I've compared it to, giving more power and better SQ. There are other cheap external soundcards out there, but I haven't listen to many, so I can't really comment in regards to comparison with them.

All in all, if you are looking for a home based hi-fi setup, the E10 isn't really the best option. For those on a budget, internal soundcards will offer better bang for buck most of the time. For those with money to burn, more expensive full-size DACs and amps are obviously going to be vastly superior. But if you are looking for something small, well made and low priced, to match with IEMs or efficient headphones, this is a great choice. It's what I use it for, and I am happy with it for that.

What they did with this card was get a lower quality, and poorly supported chip and stick the X-Fi label on it. It's not a good card.

Drivers are dodgy and completely non existent for Linux. The sound is OK, but not noticeably better than what you would get from an Audigy SE or something. It certainly isn't 'X-Fi' standard.

The only 'advantage' I can think of is that it is PCI-E. Not that it improves performance or anything, but if you only have a spare PCI-E slot and need a cheapish sound card this might be your only option. In all other scenarios, avoid it.

Oh, and you don't need the evil Creative propriety header to connect it to the front jacks.

This little amp has plenty of juice and is a good replacement for dodgy laptop sound. Just don't expect it to outperform more expensive DACs, soundcards and amps because it won't.
The interface is a bit irritating and I find myself wishing it had a volume knob, not just buttons. I find it hard to figure out which button is which without looking at it.
Generally though, it seems pretty solidly built, so no complaints there, although one of the jacks on mine has always been a bit iffy.

Sound is reasonable, a little bit of extra bass and a lot more clarity when compared with my onboard sound. I'd also probably say it sounds better than my Sansa Clip+. Clearly outperformed by a better DAC or something like an Asus STX though.
Amp is quite powerful and can go loud. I rarely push it past 20.

Certainly not the giant killer that it is sometimes made out to be, but nevertheless a good entry level product that pairs particularly well with low impedance/sensitivity phones like lower model Grados and canalphones (really good with RE0). Anything that is harder to drive or has higher quality sound really deserves better than the E7 though.