I haver (had) a KTBH and two Langs, all foundationless - I don't want someone else's dirty wax. The two Langs have cross comb, maybe because I used nine frames instead of ten, but at robbing time that really doesn't matter, as I use crush comb method. It does inhibit inspections, though. The top bar was going gangbusters, with beautiful comb, lots of bees, and minimal cross comb. I expected lots of honey from them, but, alas, when I arrived with my buckets there were just a few confused bees about and the hive was full of wax moths. I suspect the moths were just a result of something more sinister, but I had been lazy and not looked inside for three of four weeks, so I now have no clue. But to the point - the top bar hive girls followed the rules and drew marvilous straight comb.