For the past 2 winters I used Sealskins and normal riding boots (Spesh trail 110s) that were OK but the Sealskins still let in water and don't keep your feet warm. Now I use Shimano AM30 boots which after last weekends very wet ride where they let in pints of water I don't fancy wearing all winter.
Winter boots are damn expensive and most winter rides in the Southwest are above 5 degrees so are they worth or will Sealskins / overshoes / merino socks do the job.

Overshoes and Bridgedale winter socks for me.

Same as the Captain! Sealskins just don't fit my feet properly and bulk out my shoes.

I use sealskinz thermal socks and northwave celcius boots when it gets really cold and they keep my feet nice and toastie.

I normally just get away with thermal sealskinz and normal riding shoes.

2 out of 3 for me; either SealSkinz and winter boots or Sealskinz and overshoes (with summer shoes). Sometimes it would be all 3, but I can't get a pair of overshoes to fit my boots.