Glamdring... I don't agree. Heathrow, Gatwick, Stansted, Farnborough and Luton all had approach radar at one stage so the controllers had to have dual validations. Never caused me any pain during my time at Heathrow.
The original question is interesting. I loved working in the tower but when the approach side was moved to LATCC I was glad to go. I was 49 at the time and was finding the tower hard graft whereas radar was always quite leisurely. I'm sure some won't agree!