I bought a stack of them. They paint up okay, and they're a dream to convert compared to most tanks that scale.
Paint sticks well, and with a little work they can look really good. Make sure to wash off the mold release, but that's a given. The material is a hard plastic that works well.
Couple warnings:
Flash. It's ugly, and the front underside of the tank needs serious file work to look good.
Scale: These things look like 20-tonners. They do scale well with Micro Armor models, but not so well with Battletech armor.
If, like me, you're okay with packing a full 2 companies of Scorpions, then go to it - with the ease of conversion, I made several LRM and RL/LAC-5 versions then used the leftover guns to make the new twin LAC5 variant and various other things.
If you have the box set minis handy, the tank itself is about as long and deep as the body of the Catapult.