I've leveled 3 chars from 85-90 and 2 chars from 80-85 since 5.3 without any major issues.
I cannot say "how safe" it is since it's a question that can't be answered really, just bot with caution. Like you always would.
When botting "safe" is a term that is tricky to throw around. Nothing really has changed with them. They are both great. The best way to be "safe" is to not be dumb. Check in on it and don't let it run 24/7.
I just got back from a 72 hour ban do to excessive GB2 (I think). I logged into an alt from my farmer and in seconds started Kicks and ran it for 6 hours (cuz I'm a dumbass like that). Didn't have any issues. Still have the account... For now.