I would prefer to go without because I can do more with adjustments on the fly.
However, I'm not a pro bowler. I do something else for a living, and I get substantial wrist pain sometimes from bowling (due to an unrelated, very old injury). So right now I'm using one about half the time. I always warm up with it and typically shoot the first game with it at least, and this allows me to be pain-free the next day.
At the same time, I have no problems with anyone who wears one all the time. I know it's controversial to some and while I can see their argument, the fact is those things allow people to enjoy bowling who otherwise could not, or at least not as well -- and if they automatically guaranteed success, there would be 64 pros wearing them every week instead of just one (Scroggins). If anything, I think that proves they aren't the advantage a lot of their detractors claim them to be.
For those who still want to gripe even at the bowlers who use them to help alleviate pain, I'll make the following deal with any of them, but I've yet to have anyone take me up on it: I'll ditch the brace forever if you'll put your bowling wrist on top of an anvil and let me hit it with a sledgehammer.
Jess