I'm planning on getting a 29er (dawes deadeye) off bikesdirect and I'm unclear on how sizing might be different - especially if I can't test the bike in person. I'm 6'1, 35" inseam, and as far as I know my arms aren't oddly long or short for my height. I rode my dad's 21" Trek 850 Antelope and it felt just right but it has 26" wheels and a horizontal top tube. I also know my 18" Raleigh Mojave is too small. I'm just trying to pick between 19" and 21" now. Any help would be much appreciated