Yeah my bike has vertical dropouts. If it had horizontal dropouts there wouldn't be an issue. I'm not going to buy another frame though. This project was born because my old bike outlived it's heyday and I got a new one to replace it but I had been riding on my old one since 1993 (All over the northeast) and grew attached to it and so wanted to reuse the frame again in a new incarnation. (Kind of like a ummm phoenix-type thing) So I thought about a heavy-duty, bomb-proof, fast, SS, CX-type roadie cruiser for flying around my town on errands while hopping off of curbs and junk.
Anyway, I want to use the omnium because it is very stiff and is rounder than a 130 or 110 crank so should help a little bit with chain tension issues. Also because I wanted to use a larger size cog so there would be less wear on the chain. But most importantly because it looks really cool; very simple, stout and industrial looking crank and I think my phoeni.. I mean my bike would like it. But like I said: If it doesn't work I'll use something else, just want to find out before I buy it and "experiment" with it to see if it will work.