Need to change NP205 shaft??

I'm getting ready to install a Mitchell gear splitter behind the 205 transfer case in my '77 F150. I'm changing the 1310 yoke to a 1350 and while looking at different sites I saw a place that offers the yoke but also a replacement shaft that's less prone to breakage. At what hp or shock levels do guys look at changing these components for something heavier (other than the obvious "when they break"). Thanks.

Around here where we pull I've seen trucks with over 850hp not break the stock shaft in the 205 but they were running automatics. Most of the trucks that break the stock 205 shafts are 4 speed trucks with horsepower of 750 & up. I have been pulling for about 8 years or more & (knock on wood) have never broke one,but I've always ran a c6 which seems to be easier on parts than the manual trans. I'm switching to a manual this winter so I'm going to upgrade the 205 shaft. Hope this helps.-A

That was exactly what I was looking for, Thanks. I'll pick up the yoke and seals and call it done.....................although that billet cover looks pretty