I have 3 side-snap that I got from VeryBaby. Mine actually aren't fitteds, I had them made into AIOs (it's one of the available options). I can't say how they compare to the VBVeryBasicAIOs, because I don't have any of those. But they fit nicely, with lots of room to grow. I have mediums for ds and he's on the tightest snaps. He's about 18 lbs. I *think* they're trim, but I don't value trimness like some others here do, so I may not be the best judge on that. They're quite absorbant with the lay in doubler and snap-in soaker. They're very nice for running errands and such during the day, when ds may not get changed as often as he would if we were at home. I would say they're perfect for "extended daytime use." Granted that's extended for cloth (2, maybe 3 hours???), I wouldn't leave my child in it for 4 or 5 hours. But, my ds has turned into a super-peer! I hope my rambling has helped in someway. I'm still a little incoherent from the holidays.
I really liked my front-snapping VB fitteds when Avery was a little smaller. We had mediums. They performed great, were trim, etc. I got them secondhand so I'm not 100% sure who made them but I'm guessing Jess @ VB since I haven't really seen any of her contractors doing fitteds. They didn't really fit like the AIOs per se, the wings are wider, etc., but it was a comparable fit - and just like the medium AIOs, she outgrew the rise before she outgrew the snap settings. We had <img alt="" class="inlineimg" src="http://www.mothering.com/discussions/images/smilies/moon.gif" style="border:0px solid;" title="moon"> in them for a few weeks before I gave up on them. :LOL ... come to think of it, I wonder if she'd make a M/L fitted - that would be nice <img alt="" class="inlineimg" src="http://www.mothering.com/discussions/images/smilies/drool.gif" style="border:0px solid;" title="drool">.
I got some vb fitteds from Erica at Snuggle You. The fit is exactly like the AIO's and trimmness (of the dipe alone) is also comparable. They are very absorbant for the lack of bulk also. Good dipes and well made--I am happy with them (though I don't use my velcro dipes or covers that often).