I love the Henle with András Schiff's fingerings. I'm much more familiar with the old Peters edition of the WTCI, but the typesetting/engraving is pretty cramped.
I don't know if it's for beginners, but it's got the right notes, and it's got some good fingering, and the hand-separations seem sensible to me just from reading through.
That said, the only Alfred edition I have of Bach is the Inventions+Sinfonie, and whoever edited it did a great job of, it seems to me, legibly writing out what hand should do what. Pretty much the way Busoni wrote it, without all the extra stuff.
Plus, plenty of space to write your own notes.
But for a book that will last a while and keeps you free of eyestrain with that shock-white paper, my vote's for the Henle.
ETA WHOOPS! Wow. I didn't realize I'd written pretty much the same thing back in November of last year. Well, apparently, I still like the Henle WTCII.
The way I'd put it is that the Henle editions of Bach are primarily scores designed for reading, at all stages. As well as looking at the editorial notes and the sometimes interesting prefatory material. All of my Debussy purchases work great from Henle (yeah, I know, Durand &cie is the "real" edition, but I like the editorial notes and extra material offered by the Henle), and I'm about ready to upgrade the Bach keyboard concertos to the Henle editions, just for the simple reason that there can be a lot of notes, and much of Bach I'm not going to commit to memory, so it helps to have a legible edition, for me.
Plus, they're sturdy as hell for being just paper-bound editions (I know they do some hardcover editions, but I've never seen one outside of a library). I don't go anywhere without stuffing a few scores in my shoulder-bag, so that's a pretty good test of how well an edition/publication holds up. I'd imagine actual students would give similar or even rougher treatment to their scores.