As you know I have a cat D Alfa Spider which had mechanical issues only. I stand by my repair and would pass any inspection. Yes, you can get your fingers burnt but if it's been done properly I don't see the issue. Loz repaired his cars well too.
I personally wouldn't buy a super car that had been repaired but I would buy one and repair it myself.
Never had any issues with insurance neither but then again it's not a Ferrari.
You have to remember that cheap in, cheap out and it will take longer to sell.
It winds me up how lazy insurance companies have become. I look at my Alfa Spider as another one saved, it would have been stripped for parts if I hadn't rescued her.