I've not tried the other brands....but I do have both EZ Drummer and Superior Drummer, and really think that Toontrack made a couple of great products.
I had EZ for awhile, but never really used it, and then when I finally decided to mess around with it, I almost immediately added SD, and never went back EZ, though I have a bunch of EZ drum packs that I use with the SD player/mixer.
EZ is just that easy.

SD is not that hard at all to figure out, but it does give you more pro options to mess with and much more control over the individual kit elements. EZ is great if you just want a quick drum track without a lot of work, but if you want the same control as if you miked up a kit with individual mics and had each recorded to it's own track, then SD is the better way to go. I also have some of the SD add-on drum packs, so I've got at least a dozen or more kits I can now assemble from the EZ/SD packs.