I quit using bamboo period.
Because of problems or you just dont like it? Do you scrape the rind?
Well... many reasons I guess. It's very dry where I live, especially in the winter, and ALL my bamboo backed bows have checked. Regardless of what finish I've used. Doesn't cause any problems, but some of my customers have freaked seeing their "broken" bows.
Bamboo is labour intensive as a backing. Cutting and planing and sanding something round to make it flat is a headche. Hickory, maple, ash, etc., is so much easier and more consistent. Bamboo's nodes give me fits... trying to match spacing, they're weak, etc. Scraping, no scraping... some of my bamboo backed bows (as Gordon will attest) just fail for no apparent reason. VERY frustrating after many hours of work. All this adds up to me looking elsewhere for backing material. As probably 80% of the bows I make are backed, I wanted a much more user friendly material.
All that being said, if you can make it happen with no problems, a bamboo backed osage bow is probably the sweetest and fastest bow you'll ever make.
Funny thing too... the only bow I've won BOM with was (you guessed it) a bbi. Go figure!!