They sound good live, but I don't know of too many people who would want to record with them.
I had a set for years and LOVE them, but for a lot of drummers they are too bright sounding. You can put a set of Evans Oilheads on them and they will almost sound like wooden drums.
Plastic shells are a LOT louder than wooden shells because the shell doesn't absorb any of the sound;it's not porous, while wooden shells definitely absorb some of the sound.
The downside to them, is that the shells crack very easily around the areas where they have been drilled for hardware. This is why I got rid of my Ludwig kit.
Tim