Both products work great for blocking nicotine stains. There are pros and cons of both. BIN is over $20 more per gallon, although in some cases you can get a cheaper price if you buy a 5 gallon container instead of singles. BIN dries really fast with the windows open. You can paint over the primer in 45 min to 1 hour. It sprays like a dream. Both products splatter and sprinkle like crazy when brushing and rolling, especially BIN because it's as thin as milk. You need eye protection if you're rolling either onto a ceiling. I highly recommend using an airless sprayer over rolling. Cover Stain dries a little slower. It sands easier. The smell lingers. Clean up is more toxic, requiring the use of paint thinner. With BIN, all you need is a cheap bottle of ammonia and warm water. Both products smell horrible. You absolutely must wear a respirator and open all of the windows to ventilate the fumes. If it were me, I'd use BIN, but not in high moisture areas like a bathroom. Everywhere else it's fine. You can paint over it with any latex paint.