I don't know anything about megaupload except for my interaction to get the vids, but so far it's been fine (I also have a very good ad blocker, though). I wouldn't necessarily recommend it one way or the other, but if Solo has extra space going unused that's being paid for either way, they may well be willing to extend some of it to a good cause (read: more Guardian fan stuff). For my personal use I use Dropbox, but neither of those are designed for photos and it looks like Smugmug is, so it might be the best.

This fandom seems small but still quite active, and very warm and welcoming! I just joined recently myself! :)