I just got my replacement bogies, from Allen Ulmer, installed and couldn't be happier with them. I can't testify to the durability yet, but nothing can be worse than the stock ones. I've gone through two sets in two seasons and ate up two sets of hyfaxes because of them. I really don't care about the fan design pulling in snow either, that's just a bonus. As long as they last more than 500 miles I'll be happy, and I see no reason they won't.
Install was a breeze. Took about 10min. going slow, and there were no ill-fitting issues. Bolted right on perfectly.