My dad has one of these in his fleet (80th anniversar edition). Im not quite sure why? I think he said it was at a silly price, with sub 20k miles, so he could'nt say no!
I borrowed it one weekend when my prelude was out of action. The roof was, erm, crap. Its like putting up a tent, has a million clips, and the mechanism needed to be worked back and forth a few times before it would close down totally.
Driving-wise, it felt nice and balanced, and I even managed a bit of bum out action in the dry on a large roundabout. Felt quite planted most of the time, and was not boring to drive, especially with the roof down
It seemed quickish (1.8 version), gearbox was a bit "agricultural" though, and the interior looked like it had had its parts lobbed together from whatever they had lying about in the parts bins (which i suspect is exactly how MG were making cars at that point!)
I managed to get my (huge) hockey stick bag into the boot without issues, and the seats were not terrible, although I dont think i would have enjoyed any long journeys in them.
Overall, not a car I would run out to buy, but at the prices they seem to go for, it might be a canny second-hand bargain now. It was quite capable, and if you are looking for a mid-engined, British, open topped sports car... Its probably perfect