Thanks for all the replies, especially 2slo2run. My mouth is watering and I think I'm going to pull the trigger.
2slo2run, I'm wondering what cog(s) you are running. I'm thinking about a 15 for freewheel. I calculated final ratio (crank, teeth, & wheel size) compared to the 42/13 I've been testing myself with on my 21 sp hybrid. The 15 would give me a bit lower final ratio than that.