I'm sick of my homemade crappy bolt-on cog! It's not perfectly round, so I want a new one on a new wheel i'm building.

I could make it myself, but the cost of a dx cog, drills, labour, etc. is higher then buying one from Tomicog or Londonfixiebike.

But here's the problem. Which one to choose? Can you guys give me some reviews? Both cogs look really nice and cost about the same. The tomi is 25 euro's, Fixiebike comes in at 22. Yeah i know, that's cheap. It's because there's a new 3 dollar coin:




I could buy both, but being a student and all I have to restrict myself and go for one.

Help me out! Please!