I got one last year (both the target trainer & the laserlyte 9mm cartridge). I enjoy it quite a bit. I think you get used to being able to hit the smaller target. I've used my viridian green laser on it and it kinda hoses it until you go turn it off/on (or maybe hit reset, I forget). a crimson trace laser also made it not function correctly (so I couldn't use it in 380 with the P3AT/crimson trace combo).
I can tell you that you have to manually insert the laserlyte cartridge and I have to stick a plastic rod down the barrel to get it out (lightly). You can't just rack the slide & it go flying. I have no experience of other cartridges than the 9mm laserlyte one.
Overall a good product in my opinion.