Summary
 
I've had these for about a week now, and I have to say I like them more each day.
At first I was rather worried about purchasing them, because other reviews were saying that the bass was slightly subdued and the mids/highs were more prominent; I personally prefer a warmer sound, so it was a bit of a gamble buying them. However, I'm so glad I did - although at first I did feel the bass was a bit quiet, I installed Equaliser APO (http://www.head-fi.org/t/649389/a-free-parametric-equalizer-for-windows-vista-7-and-8-that-doesnt-need-asio-or-vst-it-works-inline-at-the-os-level) and after experimenting first with editing the text file, then finding a GUI (linked in the same thread), I boosted the bass to where I wanted it, lowered the treble slightly and it sounds lovely (to me) now. On my phone I use Google Music, which has a basic equaliser itself, so I did the same thing there and it's all fine and dandy.
For the price, I could not have asked for more.
 
Now to build a bit on my pros/cons.
 
Pros

1. Isolation. These headphones are fabulous at cancelling out the outside world, and leak very little sound.
2. Cables. The fact that I have a shorter 1m portable cable and a longer 3m one is great. Really useful when I'm home to have the longer one, but having a shorter one stops tangles and confusion when out and about. Although the male jack on the actual headphones is very unusual, Superlux also provide a little clip to hook the headphones to the cable, which although simple makes all the difference - often removable cable headphones can get yanked out very easily.
3. Replaceable pads. As you can see in my cons, the default pads were not my favourite. However, they're easily removable and transfer with any pads for a variety of AKG/Superlux headphones which are available pretty cheap on eBay. Alternatively, there is always a sock mod.
4. Clear/detailed sound. Using these headphones I noticed various things about tracks I had not before. Even with my bass bumped up a bit the clarity has remained in the higher frequencies, giving a clear sound picture.

 
Cons

1. Clamping power. When I first put on these headphones, I was suprised by the strength of the clamp. Being rather light, I didn't think they would clamp so hard. I had to leave them stretched over a set of books overnight to stretch them out a bit. I'm sure they'll wear in a little, but I found it a bit uncomfortable at first, though they are improving as time goes on.
2. Default pads. The default pads are pleather, and because of their fully isolating nature I've found my ears get a little warm and begin to sweat under the pads. I'm sure a sock mod would sort this.
3. Some EQ needed. As I said in my summary, I had to boost the lower frequencies using EQ slightly to get the sound I wanted. I do not feel that these headphones are lacking in bass, but the higher frequencies are certainly louder. I have tried bumping the bass way up as an experiment, and I can say that they could handle as much bass as I could give them - well, but they needed a bit of adjustment to get the bass at the same level as the mids/highs.

 
If you have any questions, feel free to PM me.