B&M Converter is bad

Brand new converter that was never run, unfortunately was in a box for a couple years so I cant return it is garbage. I have a new B&M 2000 stall converter that is junk! I have a issue with the car wanting to die as soon as you put it in gear and thats with the idle set at 1200.

So here is my question. Im looking for a new converter and not going to go with the B&M. That converter was neutral balanced and I had the matching flex plate since Im running a 360. All the converters Im looking at (Hughes, TCI, Tubro Action) are all balanced converters. Will that work with my flex B&M flex plate and will the balance of my engine be ok?