I quit riding fixed when I got laid of back in January, but I rode 42-18. My knees would act up if I went much higher than that on the flats and agony going uphill. My cadence on the flats was around 120rpm and I could spin up to about 160rpm. My commute had 400ft of elevation chance, so I would drag my front (disc) brake a bit going down.

I just built up a bike for a trip to Portland that ran the same gear range and found it perfect for myself on around that flat town. My spin was about the same, but I'm out of practice on my skidding. I'm thinking it might be time to stop riding the gearie...