My parents, pre-kids, did time-distance rallies in a TR4A.
Sold it because I came along. They loved that car. Wire wheels, cherry wood dash...beautiful red paint w/ a white interior and white top.
Fast forward 12 years or so and my Dad brings home a '75 TR6 in BRG. I only got to drive it once when I had my learners permit. They ended up selling it because I was soon to turn 16 and their stupid insurance agent quoted them what it would cost to insure me as the primary driver...I was supposed to only be a part-time driver. Anyway, by the time I had saved enough $$$ to buy one I had out-grown them, literally. I couldn't shift one without opening the door.
I don't recall the TR6 being problematic at all.