Rhoto's are all I use, only thing that works 100% for me. But the stinging part is supposed to happen it's actually supposed to make your eyes feel cool, people around here call them menthol eye drops. First time I ever give them to anyone and they're usually blazed off there ass they complain they sting I just say, "Man you shouldn't of put that many drops in man, that was acid". But I wouldn't say they're bad for you if they're supposed to feel like that. Try the blue Rhoto ice.