I was pondering this question myself as I have upload to only ReverbNation, but rarely use that site now.
And a little "rant" (well, I wouldn't call it that, but I do have a question and possibly a suggestion (to the Bakers) whether or not this'll work, but here it goes.
I haven't seen it here, but it'd be nice if you could upload files on the forum itself. (I do realize bandwith and filesize would be the deciding factors), but the MCS forum allows this.
Don't get me wrong and maybe it's a self-conscience/confidence issue, but assuming that files upload can't be taken down, that's alot of clutter to have 20 versions of the same file with subtle differences (and I know alot about this with the tracks I'm doing stored on my External HDD - I keep everything or at least most of it.)
For me, that's something I would probably do and think I have done is "redirect" folks who want to hear my tracks to the (MCS) Forum/Thread/Reply(ies) that have the files uploaded and I do believe there is a limit, but again only I have only a few members and not the entire internet community to think about.
Whether or not this eventually happens, makes no difference to me, but I thoght I'd make the suggestion.
Having said this, I may sign up for Click, Cloud or both. I don't know.