How are you riding it right now? I bought a similar bike online, fixed/free wheel, and tried both. Brakes that came on the bike were garbage, and the one time I tried fixed it was a bit much, so I opted for a new wheel with a coaster brake. Works decently enough for what I use it for. Emergency stops are hairy, but they are on most bikes.
I am hoping that over this summer, I will be able to take it out more and try the fixed gear again, as ultimately that is what I would like to ride, just for the simplicity of it.
So far its fine. I only ride a few miles to work each day. I might upgrade the brakes. I ride it as a free wheal.