The drop axel does the same as the spindle lift. I prefer the drop axel vs the spindle but have been changing my mind while looking over the Jakes catalog.
A long travel will give you far superior handling to either of the above.
So, Spindle lift, easiest to install.
Drop axel still not difficult to install, and in my opinion a little more heavy duty.
Long travel, most expensive but ultimtely worth it! again, my opinion.
You can lift the rear by flipping the axel under the leafs, no blocks required
Good luck and enjoy