I have these on order but am not too excited about them. I wish they were "real" EU characters. It would have made the set much more appealing.
Well, as you probably know, some are and some aren't (or aren't yet). Omega Squad is very much a real part of the Expanded Universe and has been around for a while, plus has actually been requested by some fans. The Mandalorians are mostly new, but they'll be in some of the books eventually. I know it's not the same thing-- it's more fun to get a character you already know than one you haven't met yet-- but from the brief time I had to futz with the samples, I dug 'em. (Especially now that it seems they made some improvements to them.)
But yeah, buy what you like. The entire collection is just so vast where sometimes it pays to be picky. I still don't really have a place for my Darth Malak figure outside saying "welp, I got it..."
I figure the "skull" clones are going to be serving as squad leaders for my white Clone Troopers. As they need some sort of organization.