Some are used at higher levels yeah. As for the "special" variations on standard utilities, Silius posted on VGC awhile back that they don't do anything in particular right now -- other than stack in bigger stacks.
This surprised me, actually -- I could have sworn my corrosive solvent and heavy bandages worked better than the standard stuff... but it's so difficult to get hard data and so easy to make subjective judgements in games, let alone in VG's complex crafting system, that for the most part now I just don't believe my eyes unless Silius tells me otherwise.
Edit - added the uses for those 4 utes to the wiki page. Thanks Greydog and the others.