I purchased the Roland TD-3 drum kit to be used in my apartment to practice drums without annoying my neighbors. Eventually I started using it to record MIDI drums in Pro Tools. The TD-3 is perfect for this kind of application. It isn't as fancy as the more expensive Roland E-Drums, but it is reliable and functions appropriately. The cymbals are the least realistic thing about playing the TD-3 compared to acoustic drums/cymbals. I think this is the hardest thing for e-drums to get right mainly because rubber feels much more different than metal. I don't mind rubber pads for drums, but having rubber cymbals is a little weird. Nonetheless, the drum pads and the cymbal pads trigger very well. They just don't feel that great. It is a sacrifice you have to make for quiet drums. The hi-hat pedal also takes a little getting used to.
Since I have had the kit, I have purchased a couple of Hart Dynamics drum pads to supplement my TD-3. These triggers are much more realistic to the look and feel of acoustic drums. They actually work very well with the TD-3 drum module. This was a big advantage to the roland e-drum kits. I definitely like being able to expand my kit as I save up the money. Eventually I plan on adding better cymbals and hi-hats too.