Faster (M5)
More respect/visibility from motorists (all of them)
More comfortable (all of them)
Safer (endos and falls)

I also concur with Cycling Monkey's experience. for some reason, a bent causes drivers to give me a lot more room. The bent's that have a mesh seat (Ryan, P-38 and now the Trice) give me the most room from cars. There was a thread on this on BROL: I attribute it to the "gimp factor". Riding a bent, particularly a trike, is associated with being disabled- no one wants to hit a gimp- so therefore cars are more cautious around bents. I won't insist on that interpretation, but it seems to fit the facts.