I am looking to purchase the schwinn moab 3. I'll be using the bike almost exclusively for touring. So, my question- I spent a few minutes on the 19" frame, which felt fairly comfortable and had a standover height of about 4". I was told I would possibly be more comfortale on longer rides on the 21" frame, which I haven't found anywhere to test but can be ordered. Any advice on which of the two to go with? As reference I am 6' tall with a standover height of between 33 and 34". Any advice would be greatly appreciated.