Yes, if installed properly coilovers are pretty safe. I have AroSpeed coilovers and haven't had any problems with them. However, if I could go back, I would've gotten lowering springs instead because I've heard they provide a better ride. Can't go back now... unless I weld some perches back on my shocks...
Basically the only good reason to get coilovers is if you're real anal about setting the ride height exactly like you want it. I spend weeks adjusting and readjusting each corner up or down 1/16" until I got it just right.
