Cross-check. Please, for the love of all things sacred, do NOT cut off the rear canti posts. You make be all gung-ho about riding fixed now, but in a couple of years, you make want to start racing cyclocross, you may want to do some loaded touring, you may want to... coast. They're really not that ugly. Stop being vain. Everyone isn't staring at you at all times. Nobody's going to think you are any less edgy and unique if they see that you have canti posts on your frame. The crosscheck is a killer frame and is one of the most versatile frames money can buy.