They aren't bad per say, but they aren't good either.
The good
Probably better light output than your stock fogged up leaky headlights
Look better?
The bad
They bounce...a lot (can be fixed, just takes times)
The light output is fair at best
The mounting bracket likes to break, especially where the bosses are for mounting them to the car (for 97-03)
Expensive
I've had the Spyder Gen 1 before.(for the 97-03 cars) I think they look good, but the chrome corners kind of suck. Even with a good quality HID set, the output isn't very good from them. Took ages of testing, fitting, using zipties, foam, etc to get them to not bounce like crazy.
Retrofits are a MUCH MUCH better option. Either make them yourself (there are a few VERY good writeups that detail every step) or browse the for sale threads and buy a pre-built set. The light output is amazing. They look the best (in my opinion) and are by far the best bang for the buck.
If you really really just gotta have the halo projectors, go for it. If you feel like you want really good headlights that are brighter, aimed way better, less hassle, and better quality, look for a retrofit. (I've been rocking mine now for about 9-10months, and would never ever use anything else.