I own one of each. (Woods BB840 - Bush Hog 286) All things being EQUAL, I'd buy another Bush Hog. Everyone raves about Woods and their easy to remove blades. In 35 years of owning every sort of mower I can imagine, I've only removed blades ONCE. ( I sharpen blades in place) So that isn't a high priority in my book. My most recent Woods (the BB840) has paint issues. (It's peeling off in sheets) It has a tendency to leave grass/weeds standing in tire tracks. The Bush Hog, mounted on same tractor, cuts cleaner. (No logical explaination. Don't think it's a problem common to ALL Woods mowers, but who knows?) Another dislike I have for the Woods, it seems to blow chaff out from under the front end more than any mower I've ever used. (BOTH have nearly IDENTICAL saftey chain guards) In a few hours of mowing, I'm covered with dust and grass clippings. The Bush Hog doesn't throw any clipping out from the front that I've noticed.
Both run almost vibration free. Both are top quality designs. (Agian, my PERSONAL choice being the Bush Hog) Being a 6' and 7' models, there isn't a good direct comparison, but in general, I prefer the Bush Hog as I mentioned. (Only real commonality, both are MEDIUM DUTY models from their respective maker)
When I bought the Bush Hog, (Jan. of this year) I priced both brands. The Bush Hog was $260 CHEAPER. When I bought the 7',(Woods) in June of '04, it was $100 cheaper than Bush Hog 7'er at that time. All depends on when dealer bought their stock of mowers from manufacturer.
Bottom line, you won't go too far wrong with EITHER brand.