I never said it wasnt, i know how capable a hp44 and 9 are. But waggy 44s are lighter & cheaper, and when your dealing with a lightweight, low hp rig, that matters a lot. He could stuff waggys with 5.38 or 5.89s under a hard body and wheel the heck out of it. Im not sure if they run doublers or anything in nissans, but thats also a thing to consider with axles and gears. I know your talking about a cage and exo and what not, i would build what you have now and worry about that later, im not a fan of exos at all, all that does is add weight, especially if its just gonna get beaten. If you want an internal cage, some company may make a bolt in or weld in cage, if not tommy glenn seems to do very good work for a reasonable price.
Are you gonna keep it on leaves? My votes for waggys with leaves and keep it low on 37s with a 4cyl and 5spd. Simple and itll work.
http://www.nc4x4.com/forums/showthread.php?t=109224