So like my previous post.. put money down for a rail 9.7. Trek sizing says I'm ML. I rode both a med and large and can't really tell the diff. The shop said the large looks good because of full leg extension?.. a large won't be available till maybe end of January according to the dealers site. A med just came in.. will I regret going with a med? Is it possible to maybe change to a longer dropper, or diff bars, crank? To give the feeling of a large frame on a med frame?.. sorry this is all new to me.. never had a mountain bike or any bike for that matter in 20 years.. should I just suck it up and wait for the large? Thanks