I snowshoe a decent amount in the mountains behind my house during the winter. One of the biggest things I notice is that when you have a hardpack of snow, with not a ton of powder on top, snowshoes work pretty good because they have something to compact the new snow onto and tend to not sink so much. If your on a lot of fresh powder though, prepare to get worked, because although they distribute your weight much better then just boots, they still sink.
Like everyone has said, snowshoeing is very athletic. It's a bit like hiking in sand. If your going a long distance, carrying lots of shit on your back, your going to get tired fast. That being said, I think snowshoes will probably serve you well for your first several smaller BC experiences, just to get a better idea of what it's like because just going out and buying a split is expensive. Once you decide snowshoes suck and you want to do lot's of BC, get the split.
Having a pair of snowshoes anyways isn't a bad idea. I have a pair simply because they are necessary where I live if I get snowed in, have to park my car down the road, and snowshoe to my house.
PowderHound and TreeNinja