Hi in my opinion a 22/18 or 24/19 or 18/15 etc all the same. There is a few issues I'm trying to solve...my kranks are shimano xt and 22t chainring. This leaves 2-3mm of clearance for the chainring. Hence I would like a smaller one up front, but I don't think they exist... A 22/17 current setting gives minimum chain slack and gives me the option or running a home riged chain device. But I was just interrested in what other people where running. But for some reason must of you UK guys hate inspired...ride on