I Does the weight of the comb pose a probrem on the bars? I'd heard that it was fragile and easily broken off.
With some simple precautions it is not a problem.
I made these hives big enough to hold a Deep Langstroth frame hanging from the bars so that I could move nucs into them with them having to start from scratch and interrupt the brood cycle. I think they are like 22" bars and the hive is like 15" deep. Pretty good size combs.
I have never had a problem with comb failure on these hives. Just never try and hold the bars in any position other than vertical. This can be a hard habit to break if you are use to flipping langstroth frames over the inspect the back side. The easiest thing to do is build a simple stand to hold the bars as shown in the next photo.
Although the barrel hive frames are about the same width as the other hives, they are only about 12" deep and rounded so they are a lot smaller than the others.
The only comb catastrophe I have had is with one of the barrel hives while moving it on a trailer. The comb didn't break from the bars, but the bars slipped sideways and they feel into the hive.
Another thing is to be sensitive to the temperature when you work in the hive, especially when the comb is new. Don't go into the hive in the middle of a scorching day, do it in the morning or late afternoon.