What's your favourite gear ratio?

It's pretty hilly where I live but I had always been under the assumption that anything under 70 gi was gearing down. It's all about personal preference I guess, ride what your comfortable with.

You are right it's personal preference (or even just what you feel like, I've ridden 60gi and 80 and enjoyed both), but my point was more about scale, one or 2 inches difference (ie 68 compared to 70) is not much different at all.