OH press hurts my wrists also when I go heavier. I normally wear 24" Convicts when I get over 155 or 165. I still do the majority of my working sets without them. But it will save a lot of unnecessary wear and tear for those few heavier reps.
I had a pair of
these and sold them. I liked them just as much as my Convicts, but I didn't need 2 pairs. These are cheaper. I couldn't tell a difference in support between the two. APT has a 10% discount right now on everything in case you decide you want to order a pair. As far as length goes...12" is too short IMO. 24" is nice. 36" is awfully long. If you don't want to drop the money on a pair right now, just PM your address & I'll mail you my pair of 12" wraps that I don't want or use. They will work better than nothing.