Once you have hives with combs in them, I find that that comb guides are not as useful as before. I still think that the beveled top bars when at the right angle produces a superior attachment because the bees can maximize the attachments, but I also find with as much woodworking as I do now to make new hives and top bars, its just not as worth it as it used to be.
I am on the other hand, not ripping the bevel anymore, but using a router which is new, and so that might end up making it worth it again for new hives. But once again, once you have nice combs, and most of your top bars have been used by the bees once, you have natural comb guides in the form of the midrib attachment left behind when you cut off honey combs at harvest. THe bees just build right back on top of that with almost 0 failure.
Scot Mc Pherson<br />McPherson Family Honey Farms<br />Davenport, IA<br />BeeWiki: <a href=\"http://beewiki.linuxfromscratch.org\" target=\"_blank\">http://beewiki.linuxfromscratch.org</a> <br /><br />Pics:<br /> <a href=\"http://linuxfromscratch.org/~scot/pics/bees/\" target=\"_blank\">http://linuxfromscratch.org/~scot/pics/bees/</a>