Continued Demon troubles

I posted some time ago about the problems I'm having with my Demon 525. I'd link to it but I can't find the post. Anyway I finally got upset enough to call BG and complain enough to have them take it back to check. I just got it back last week and re-installed it, guess what, it's still a P.O.S. The tech that worked on it said they repalced the metering plate, floats, and needle & seat assemblies. Everything else checked out fine. Well the idle quality and drivability are better but now when it's cold out, raining, or generally below 70 deg. outside I can barely get it to start and when it does the surging and power loss make it undrivable :damnit: . W.T.F......... anyone have a Holley 1850 they want to get rid of??