I def like bumpy wool b/c C outgrew one, I sold it and missed it so much I bought another. B/c its hand-washed (although can be machine washed, another def plus for newbies!), normal i-hate-velcro rules dont apply. Its nice and soft velcro...I don't think it bothers C at all. W/ bumpy you could also carry the PUL covers too, so the brand offers nice variety. (I don't know if stacinator has that too, just saying its def nice bumpy does-- although I've never used any of the PUL ones on C)
I've just gotten our first stacinator, although its old, toddler-sized and for the bedwetter (wool flannel I assume). I like it, but just started using it last night so not sure if I can give it a total vote of confidence. To me it basically looks like our SP, another brand I have loved using on C. I would still vote for bumpy over stacinator... vs SP might be a tie, depending on Mom's attitudes about velcro.
Aristocrats are very nice (just to throw another mass produced one in the mix).