I agree with snake regarding deep snow. And like him I prefer skis. They don't sink into the snow as far as snowshoes. (Try it, ye unbelievers.)
If the terrain is flat or merely rolling I use my narrower Norwegian army skis, the "Combi-Combat" white skis made by Asnes. Climbing skins may be used if I'm pulling my pulk sled up hills. I use old, heavy leather backcountry XC ski boots with these if the temps are above 15 F.
If it's steeper terrain I use my wider, shorter Atomic TM 22 skis with climbing skins for steep uphills. For these skis I use Scarpa T3 plastic boots.
BTW, when skiers go with snowshoers ALWAYS put the skiers in the lead to break trail. It's far easier for the snowshoers and the skiers B/C skiers have a hell of a time using snowshoe tracks.
With both boots I listed above I use a VBL (Vapor Barrier Liner) of divers 3 mm neoprene sox over thin Polyester pr polypropylene socks. This keeps my feet much warmer than even heavy wool socks and keeps the boots dry and warm. I prefer US Divers brand neoprene sox as they have fitted Right and Left sox. they come factory seam sealed, saving me the trouble. VBLs keep your sweat from compromising boot warmth, even in uninsulated boots.
Eric B.