I'm a big fan of wood stocks on rifles, but on the 10/22, I'd go with the stainless. The reason they (almost) always pair a synthetic stock with a stainless rifle is for moisture and elements. The entire rifle is covered that way.

In my humble opinion and experience, Ruger is an Outstanding company. You're good to go either way. Me? On the .22 LR rifle that's going to see alot of "banging" around? Light enough to lug around, rain or shine? Stainless / synthetic. Save the blued/walnut for your first Ruger #1....