Thanks for the great links you provide. Very useful information. I hadn't considered a bike fitment, I've always thought I'm too casual of a rider (600-700 miles a year) to warrant that. But having read what you mentioned, it may be one of those things that would benefit me in the long run. I may consider changing the chainrings, I just thought going full Shimano 105 would be good, but probably mostly for the uniformity and marginal drop in weight.