Honestly, I really like the arios... and while I wouldn't say they're zero maintenance, it's pretty much just rinsing the diffuser.

Diaphram air pumps lose flow pretty quickly as the pores in the airstone get slimed/clogged- the arios seem to maintain full flow a lot longer.

Disclaimer- I have zero personal experiance w/ the little Arios- I've personally only used the four. However, I can state that the fours are awesome.

It really doesn't matter how you get the air in there, only that you do. Go with your judgement on what's going to get the most air in there w/in budget.