You'll think they're great...
Then one day you'll wake up and say to yourself "I need to build myself a full-on, high-fashion fixie to optimise my full-on enjoyment of this excellent cycling life in the city I am so proud to call my home".
But you will be unable to render your wonderful steed into a fixie, because that stuff doesn't work right with an oval chainring.
So don't do it.
It will shatter your dreams at their very core and turn the daylight of your waking soul to darkest night.
Unless you're unlikely ever to want to go for a fixed-gear bicycle that is....
In which case, why not?
In the Sheldon Brown article linked to above he says he uses oval chainrings on a fixed gear bike.