the truth about 700r4's ??

[no1udknow]

Hey guys, I have read many forums about 700r4's and I feel like many of them are blowing smoke up my a$$. Who is running one, and what kind of milage are you really getting. my current setup is a 350 (383) with a edle-brick 750, th350 and 4.11s. I need to be able to drive this thing to work once in a while with out selling any organs. I'm not expecting the fuel economy of a sub compact, but I would hope to be able to achieve the high teens if not 20mpg by swapping the carb, rear end gears, and the trans. I have access to a 700r4 which is why I'm asking. but I might be open to other options if they are cheap. 4l80e's seem to be expensive as are t56's