I've been smashing this kit for about a year now, and I still love it as much as when I got it. It's an amazing piece of gear for the price, but I do have a few criticisms.
The hihat pedal is unfortunately terrible, and will most likely be the first part you swap out.
The sound selection is pretty limited when it comes to real drum sounds, and you will have to do some in-module EQ'ing, compression and so forth to compensate. Thankfully the processing options are pretty good, but not like you'd find in a high-end sampler. You can't import sounds either.
All that being said, you will not find better quality or playability at this price, and if you want better sounds you can play through a VST on a computer. I've used it with Studio Drummer, and gotten around 5 ms latency - better than my audio interface can manage. Wonderful piece of gear.