If you go back to the original post the question is at what height will you start to have drive line issues on the lo pinion axle. Not at one point in the thread did I ask what axle should I get.
The whole "to lazy to search" thing started as a joke because every time I get in the modified section all I see is another title for the same question asked 2 threads ago. My fault I forgot to throw some sort of smiley in there.
And by the way throwing money at an axle is parts amd material to beef it up not paying someone else to do the work for me. So next time you think your knowlegeable enough to reply read the post rather than skimming through it.
if your planning to keep your 30 as the original post stated:
TJ guys lift well around 6.5" running stock LP30s and 44s, they are plenty capable. but most serious TJ owners swap LP30s our for at least HP30s and the current trend is less lift with highline fenders. john D wheeled his 30 on 35s with stock (i think) shafts. i cant say if hes ever broken one (one reason for his 44 swap was the piece of mind) but it seemed pretty capable to me.
there is always the super 30 kit that upgrades you to a 30 spline shaft and super beef u-joints. ive seen two accounts of them run on 37s with no issues, at least they never broke around me. but even with a super stout diff cover, full case locker, and heavy trussing im not sure if id trust it up to that big. your R&P is your weak link at that point.
as far as the rubi 44:
which rubi are we talking here. the TJ 44 is nothing but a 44 center section, everything else is pretty much D30 to my knowledge. im sure it could be made stronger than a super30, but why? just to gain the bigger ring and pinion? then youve still got a LP axle. take a look at the link i gave you for some front axle ideas.
now, the JK 44 is a whole new ball game. it may be LP but the R&P is as big as they come. ive heard stories of it handling 40s once polished, but thats not a personal account.
you really need to consider what you want out of it. full width? narrowed? whats your budget? how much time can you devote to it? do you have an ETA of when you want it done? there may be an axle better suited for your needs than the rubi model, or maybe youve got a killer deal lined up on one that we dont know about. either way, you have options if you have money.
(but i dont know anything... so dont worry about anything i wrote)