The MGA was OK never had mates having trouble with it.
The B was an engine that was used by race teams type of car racing because it was a reliable lump by all accounts.
My MGB.gt with the 1800 B engine overdrive on 3th and 4th leather seats, sunroof was a trouble free car for the 6 years till sold at a good s/h price, only the wire wheels were a pain keep having to true them up.