Jim22cm: I've been using Veet or Streps for a while (two of the bigger brands in Holland) and I didn't have a problem with it. The directions also tell you to test it on a small piece of skin !! and wait at least until a day after it to see if your skin becomes irritated ...

I used the inside of my arm to test it, that too is a sensitive piece of skin !! If you don't have any irritations, you can try it on your cock/scrotum.
Do'nt leave it on too long ... try 5 minutes first, 10 minutes the next week ...