trail gear only tests theirs at 30 degrees and longs are done at 40. that in its self should tell you that they are not even in the same league with each other. if you are looking to save money you can look at a birfield eliminator kit. ive been running one long before the the longfield craze was around with 37"s and beat the ever living crap out of them and have never broken them. knock on wood. longs are pretty sweet and if ever needed to upgrade again i'd probably go with them but the eliminator has served me well and its cheap
if he wanted to do his own thing he should have come out with a shaft that didn't look exactly like a birfield joint.