Most of my electrical work has been on Japanese bikes, I've always tried to use matching uninsulated crimps and covers. I'm like others up there, if I see insulated crimps or scotchlocks I'm likely to take them out and start again.
Can't argue with that. There is no good way to fit them, they always result in cable damage so I'm with you. Insulated crimps you can get a clue from the way that they have been fitted and crimped, cable size to terminal type especially. A decent crimp pattern and sensible terminal choice would not likely cause any issues.
I had a bit of a touch a few years ago, motorfactors we do business with were changing suppliers of crimps and one of the guys working there was decanting all the shelves of crimps into a shopping trolley (literally full of them). I asked if a cheeky offer would buy them and he said go for it because it would save them marking them off to return them, £120 for the lot.
I've seen so few fitted well I'm not inclined to bother checking. With a bit of care you only shorten the cable by 6mm or so.
The worst bike I had for electrical problems was a Guzzi. None caused by the OEM stuff, all were the result of a bus mechanic's work, the previous owner.