I stick to Undernet because I have other channels there, and don't want 3 or 4 different server/status windows open at once. It gets annoying having to join multiple networks every time I hop on-line.
And yes, channels always start out small and gain members over time. That's the nature of IRC. This is particularly so when dealing with a niche group of people.
This is also the only place I mentioned the channel that's less than a week or so old now.
I suppose if I put a post up in road and MTB cycling forums, it'd get more hits.
This portion of the Forum doesn't seem to get much traffic.