I'm running a 80 rear with coils, although leafs would work fine. I actually went all the way to a four link when building a good anti-wrap.
There are many, many good reasons to run an 80 rear. There are no real alignment issues.
I sold the 80 front and went with the 55 axle for a few reasons. First, it's worth a lot to the mini guys. That money can pay for a lot of ways to make the stock early axle better.
Second an 80 rear third fits great in a 4x/55/6x front.
The 80 birfs are great, but Bobby Longs 30 splines are better yet. and he now makes long spline long sides so you can run 80 lockers. Between the longs and the 80 rears I don't even give axle breakage a second thought with 36s.
The spring perches line up, the 4x4 Labs steering works well, no oil pan problems with the high pinion, etc.
That being said, I don't have an issue with running an 80 front axle on leafs. I'm really not sure about this particular one. Too tall, z link, welded leaf studs, all the stuff that's been said. It can be fixed, mostly by lowering it a ways.