If you have the budget the 30-spline set will keep you from having to fix them on the trail. Unless you really hammer on things with large tires the 27-spline Longs should also be excellent, even with stock inner axles.
30-spline Super Set $635 from Marlin or Bobby Long direct
27-spline Set $550 from Bobby Long direct
27-spline Chromoly Birfield only $390 from Bobby Long direct
The botton line is that all three are a good way to go and depending on budget it is only
$160 for upgraded chromoly inner axles
and another $85 for the