I agree, knit in the way that you enjoy most, and suits you best. I like the efficiency of Continental knitting, but if I were really into speed I'd use a knitting machine! LOL! Really, it all boils down to what you enjoy, as Roxanne says.
As far as patterns that knit up quickly, go for a bulky yarn sweater, or a kid's sweater in worsted weight yarn. There are a bunch of bulky yarn sweater patterns in the "Chunky Knits" book linked to near the bottom of the main patterns page, and they're about as nice as you can find, as far as bulky sweater patterns. Also, if you're a faster knitter than purler, you may prefer to knit in the round. You can adapt any pattern to have at least the bottom, up to the underarms, knit in the round. Raglan and Yolk sweaters are often knit entirely in the round; at least that's how Elizabeth Zimmerman did it, and it's not hard to do if you can find good instructions.