I broke two sets of 4.30 gears, and the 5.29's I broke were from what I believe was an install error. The side adjuster just pushed out of the threads. Only reason ring gear teeth broke where because the pinion was barely touching the edge of the teeth.
5.29's are definitely weaker than 4.88's on paper, but that extra gearing helps with throttle control. I'll take the extra torque over the small amount of strength gains. 4.30 gears are supposed to be even stronger than 4.88's, and I still broke two sets...
Only old people and wanna be racecar drivers think that a standard manual trans is better...