I just bought one and WOW!!! Nick set it up for me (Great job by the way) and it is sooooo sweet. My answers to your questions:
What it is like to fire: Shoots great. I have the Voodoo Delrin Bolt and the Voodoo Full Flow Vertical installed. It has virtualy no kick and from the little paint that I have shot with it, (I was shootin' it fast) I had no ball breaks.
Maintenance: All you have to do is lube the valve and since I have the Delrin Bolt that is all I have to do for maintenance. If it messes up, you can send it to Nick and he will fix it guarenteed (Smart Parts customer service rules).
Trigger Pull: A little sloppy when you first buy it, but I have made the proper adjustments and now it is like butter. I can tell you how to lighten and shorten it if you buy one. Quite easy.