I'm a fan of Spider Grips. They last good and are easy to hold on to.
I have tried grip glue and paint.
What workes the best for me is friction tape.
Wrap the bar with the tape (make sure it is fresh - some shops the stuff has been on the shelf too long).
Wrap 1 layer and the grip feels normal, 2 or 3 layers makes the grip larger in diameter.
I use 3, since I have big hands and hate small diameter grips.
Once the tape is on, it is time to put on the grip.
Spray the tape with brake or carb cleaner.
It makes the tape slimey - slide on the grip.
You have a while to position it, you don't have to be in a hurry like that damn grip glue.
By morning it is set. The grip will not move.
I have had paint and grip glue come loose after riding in rain storms.
This has never come loose - ever.
You will have to cut the grips off to replace, but the tape under the grips comes off the
bars pretty easy.
Re-apply tape, spray and put on the grip.
Plus Friction tape and brake cleaner is cheap and you always have some of both in your shop.