I have quite a few boxcalf bags, and while it does scratch and patina over time, it's by far my favourite regular leather. Having said that, I have sent many of these bags tp FSH to spa, and let me tell you, the idea that H can get box looking almost like new again is a furphy. I'm really anally retentive (LOL) about my bags in general (although I'm all for bags that get used, and LOOK like they get used), but bumped boxcalf corners and things like deep scratches just can't be re-furbed.
If you can live with that, it really is the most special leather. Just heavenly.
I'm not sure what the word "furphy" means. But I do know from personal experience that once horribly worn corners of a very old black box back kelly (sellier) came back from the spa looking brand new. A lot of the existing deep scratches (as I stated above) were covered, but not erased, but the old girl looks nearly perfect. I have already added my own new scratches to it.
One of my recommendations would be if you were to consider box, never, ever, carry the lock and clochette, because the lock can scratch and the keys can make their way loose from the clochette and scratch the bag. That was my theory on my bag. Also, I would not carry a cadena on a box bag that you want to keep pristine as possible. That's just asking for trouble and scratches on a bag that you want to keep unscratched!! But, it will scratch and it will grow more beautiful every time you use it.
I was told by the craftsman that the repair would bring the bag back to 90%. Not bad for a bag nearly 40 years old.