The Jessel belt is much better, i havs a Comp cam 6100 on my 434" and the problem with them is they only have 3 screws to hold the drive to the cam hub on the large gear, and on the one i have it stripped the hole out with the splined screw. I had a Jessel and sold it because i had already installed the Comp unit (hind sight is 202/20) the Jessel had 4 screws and larger dia. i know it cost more but the value is there.
Zip.