I suppose that it would depend on your measurements (height, inseam, arm length, etc...) and personal preference (if you would prefer a more compact or stretched out cockpit)...also, I guess that there may be some tradeoff between handling and stability given the change in wheelbase. Having said that, I had to make a similar choice (being 5' 10.5" I was between the 23" and 23.5" sizes...I chose 23.5" w/110mm stem). Of course, you should discuss this with Charles, but I would recommend going with the 23" fram an 100/110mm stem.