I didnt even think about the 2wd being lower than the 4wd, but that makes total sense...
I did the steel because of the durability factor, I know that I won't have to worry about them. I could see the polymer spacers squeaking, but I haven't dealt with them at all so I don't know for sure.
The only difference in the leveling kit maintenance wise is that you should make sure nothing rubs anywhere in the suspension after they are installled, mine was close, and i had a mechanic that did a brake job for me tell me that I shouldn't jump the truck or do anything that would rapidly extend the shocks because it might break something important, like the springs... lol. So yeah, keep that in mind
