Yeah, as above, it’s a really tough route, in terms of climbing, conditions and distance. Stunning in places, though I know people who’ve done it in near complete cloud cover and seen nothing.
I’d say it’s not something to be undertaken lightly, you’ll need to do a lot of training and spend a lot of time on the road bike. I’m not sure I’d be borrowing a bike for that kind of distance, I’d want to know my position was dialled and that I was 100% comfortable on it, you can only know that my spending a lot of time on your own bike.
Only you can decide if that’s something you want to do.