Things I liked: This gun is fantastic! Very easy to use, accurate, and a whole lot of fun. Quality is excellent. It is easy to tell when it's time to refill the tank, since the pellets do start to noticeably slow down and drop. I use mine mostly to upkeep shooting skills without having to load up the real guns to take to the range. This gun isn't silent by any means, but sound level is very acceptable in my neighborhood (and none of the wildlife around seems to be spooked by it).
Things I would have changed: Wouldn't change a thing...it is pricey but the design and function seems to justify the premium price.
What others should know: Nice to have zero recoil...with a sharp eye, one can see the pellet impact (or lack thereof if my last instant movement pulls me off target) using the scope. Very quick and easy to reload for the next shot without having to come off target.