Gee, I don't know how I missed this post.
Personally I would not buy any flooring from a box store.
That said I have clients who maintain their bamboo with humidifiers which have not had any issues for years now. Yes, even generic bamboo. Maybe they are lucky I don't know but I advise all my clients to at least try and maintain a level of rh in the home as close to 30% as possible. Some listen some don't. Some have some minor checking and splitting, those are the ones who have decided not to keep the rh up. Some have not had any issues even without using a humidifier.
If I were you I would buy a natural stained bamboo with an AO finish, not a carbonized one if you have kids and pets as it indents easily. There's some pretty new cool floors coming out like corkboo, click stranded etc.