I suppose anything will feel heavier than those Continentals but I haven't really noticed the extra weight. Fuel economy is only about 1-2mpg less, more noticeable during in-town driving vs. highway. On my 62 mile interstate commute, I didn't see any loss of mpg.
Ditched the Continentals and went with a fairly new tire in 235/65/17. Very happy with the look, the ride and the off-road capabilities. These did great in the outback of Wyoming and are nice and quiet on the highway. The 65K tread life is a plus as well compared to some older designs...