Besides the Robo Cop type of wrist braces that are adjustable, I have a question about the other braces like the Mongoose that keep the hand and wrist in (I'm guessing) one position.

Isn't a bowler at a disadvantage if he/she can't adjust their roll?

I move my fingers in different positions to adjust, so I'm guessing bowlers can do the same when wearing these braces. But, I also adjust my tilt which requires me to adjust my wrist position. How does someone lower or increase their tilt when wearing a certain brace that seems fixed.? I'm guessing they can't.

I find the Mongoose Lifter to be very versatile.  I am able to adjust my roll quite a bit, depending on my need.  The Lifter has a half inch strap that keeps your fingers in place.  However, you can strap in any number of fingers tightly or loosely or none at all which allows for numerous finger positions.  In addition, the wrist support the Lifter provides does not leave you in a cupped position - it just prevents your wrist from breaking back too far.  However, if you want cupping Mongoose sells an insert that will give you that too.