Hello! I know theres been a few of these questions, and people have been saying the 1600, but my question differs a bit. I am a small guy, 5'8 and 150 pounds but fit. I was leaning towards the 900 because of that, but I really do not want to replace it in a year or two. I will be using this bike a lot, mainly commuting but also highway riding. Oh and I am a new rider, taking my BC1 course next week then buying the bike shortly after. So what do you guys think ? will the 900 be enough for years to come for someone my size, or should I go for the 1600 ?