RE: Mrs Gasket fuel pumps
Lots of commentary about fueling systems here on RCU. Search for"the best fueling for gas"
However, the big problem for me with electric gas pumps is the danger of sparks and explosion. In a car application there should be no fumes around the pump and lines, and the switches etc are far removed from the fueling pump action. For RC use, I would suggest a spark proof enclosure and switches for the pump and battery. Also not all car pumps can be reversed to pump backwards for defueling. Again the thread cited above talks all about that.
I have a SU electric pump from a Austin Healy that I have been tempted to rig up, but have not because of the above hazard.