For me it really depends on the route I'm sailing and the wind direction, of course. At 20 knots or 20 degrees heel, I reef. Depending on what the wind looks like doing, I usually reef the main much more than the genoa. That's mainly because its a lot more effort to reef the main, than roller furl the genoa. So rather than reef the main twice or three times, I often go straight to the third reef and keep out more genoa.
On the other hand, down wind, I tend to just roll in the genoa to start, if it looks like less than 30 knots. More than that in prospect, I remove the main and later furl the genoa. I usually prefer tacking down wind to reduce roll and bad sail behaviour.
Last year I did a lot of sailing on the genoa alone, but then my boat goes fairly well to windward on genoa alone.