The IRO kit is just fine. I have IRO cranks and hubs on one of my bikes and have no issues with them at all.

Some are going to say that you need some fancy cranks or hubs, but those are the same youngsters who are going to become yuppy BBQ and handbag snobs in a few years. I'd ignore them as there seems to be a large fashionista contingent among fixed gear riders at the moment.

If you really want the fancy stuff wait a few years until FG is out of fashion and snap it up cheap at the suburban garage sale of your choice.