The Pro Armor wrist is a high quality wrist strap, the kill-witch clip anchor and Velcro strap are highly developed and more than adequate, I place my life on it every time I run my bike. The only negative is it is a bit short around the wrist when it is used over a leather jacket and gloves full gauntlet.
Racing xc it's nice to be able to get off the bike and be able to move it and not come unplugged. On the chest protector you lose that valuable movement that can make or break a race. I ordered 3 just to have as spares.