The best tire dressing I've used is from Stoner's. Spray it on a foam aplicator and rub it in. I think the problem with any spray on is if you just spray it and dont rub it in it will get on your paint. The key is rubbing it in.
Stoners advertises their wont sling even if you just spray it on. Adams is also coming with a new product, watched the demo on that yesterady and it looks really nice, its water based and pretty much water proof at the same time. I'll pick up a bottle when I'm in Carlisle and try it but for right now I'm a Stoner's fan.