The funky taste after a few uses is rancid coffee oils. See this site

http://www.sweetmarias.com/prod.coffeecleaner.shtml

sorry it is a commercial site, but their carafe cleaning tablets stripped a years worth of coffee oils off my stainless thermal carafe, leaving some of the best tasting coffee I've had in more than a year.

Ceramic mug for home for best flavor and cooling to fast consumption temperature, with a loon on it because, well, I am, and proud of it. For away from home, Nissan 0.5L stainless thermos with a flip-top drink through lid. Put the coffee in at 8 am, still hot at 2 pm when the post-lunch pass-out hits. Fits in a backpack next to the books. Survives multiple drops on the floor.