At your team weight (which is about the same as ours) I'd be scared to even contemplate 28's. Peter White recommends strongly against 700x28 for a team of our weight. Many of the respondents to your query are lighter than you. You've already blown out a set of 700x28's. Having a tire blow at 40 mph in a downhill turn is not my idea of fun. The 28's aren't faster, so why risk it?

Panaracer Pasela 700x32's with wire bead (non-Tourguard) can be bought for about $15 apiece. They're nearly as fast as the Grand Bois tires mentioned by "reversegear" above. I've ridden on them for about fifteen thousand miles on my single bike and for nearly 4000 miles on the tandem. (I've ridden about 5000 miles on Grand Bois -- they're very nice tires, but at $50 a pop, I only use them for time-critical rides.) We run the Pasela's at 95 pounds. Because we're now doing brevets that go into the night, and we're running sidewall dynamos, I've switched to Schwalbe Marathons. They've got more robust sidewalls, and you pay for it with a slower running tire. Still, we finished our 300K brevet (190 miles, 11000 feet of climbing) on Saturday in 15-1/2 hours, which isn't too bad. We were not fully recovered from the previous weekend's 24-hour, 230 mile fleche ride.