I've added up the weights to figure out what the difference would be. If I carry the three lenses, 55mm, 80mm F/2.8, and 150mm, the weight would be 945g. If I carry just the 55-110mm zoom, the weight is 800g. Not a massive difference, about 1/3 of a pound. The real differance would be in using the camera with the lens mounted I suppose. 800g on the front of the body versus 420g with the heaviest prime. It would certainly free up a fair bit of space in the bag though.
I'm glad to hear you like the 55 field of view MattKing. Zoom lens or not I'll be sure to get a 55mm lens in the bag.
Jon, you decided to sell the zoom lens. Did/do you have primes to cover roughly the same range? Did you just not often use the range of that zoom?
So far, the zoom lens isn't looking good. I shoot mostly primes when I'm shooting 35mm so that's not a big deal. I've never been afraid to zoom with my feet
Thanks for the input!