Recommend check out the State 4130. It's a fantastic double butted CroMoly fixie/single speed steel frame bike for a great price, $450 USD which is less than half the price of the Wabi Classic. I had a Wabi Classic and sold it because I didn't love it and bought the State 4130 Matte Black which I enjoy much more.The 55cm (5'7"-5'11" riders) frame should fit you perfectly at 5'8". I am 5'10" and sized up to the 59cm State 4130 which is perfect for me.