Things I liked: Love the rifle. So far I have been very please with it's constancy. Fit and finish has been wonderful. Love the fact that you can adjust the velocity.
Things I would have changed: The barrel so far has been VERY picky about the pellet. Still haven't found a pellet that will perform well at 50 yards. I haven't given up! ;) I own the .22 version. I hear the .25 version is not near as picky. Be nice if crosman would check with Green Mountain about making the barrel for the .22.
What others should know: Patience with the pellet process. It will work out! If you choose to use a pump, like I did, be prepared for a work out!
Things I liked: Very easy to use, with one exception I will mention below. I basically took it out of the box and started using it.
Things I would have changed: Nothing, this is a very well thought out design.
What others should know: If you are using an air-gun, like my Marauder, it's best to give it a little more distance from the muzzle than you first think you would need. I started with about 3 feet and it was giving me funny readings. I moved it to about 5 feet away from the muzzle. It worked well then. The problem I mentioned above came up at this point. It is hard to line air gun up with the sensors on the unit. I was advised to use a bore sight to line it up. I haven't tried that. Don't have the money for one. If you are going to "tune" your airgun or you are in a country that muzzle energy limits, this is a must have!