UKC

Asking for a friend (Honest!) - who asked which boots I would recommend for a summer ascent of Mont Banc?

I climbed it in the 80s in a pair of Koflach Viva plastic boots, and again in the 90s in Nepal Extremes, so I don't think I'm really in a position to recommend from experience.

I'm thinking the Nepal Extremes are a overkill, and that modern boots and thinking will be lighter (and cheaper?)

What would the modern day alpinist recommend?

The best boots are the ones which fit you. Obviously they should be proper mountaineering boots and compatible with your crampons, but everything else is secondary.

Scarpa Mont Blanc of course

Seriously, I have attempted MB twice, first time in B3 boots (Scarpa Phantom) and second time in B2 boots (Scarpa Charmoz) via Trois Monts route .   B2 boots were absolutely fine and much more comfortable than B3s.  Not sure I would want a B1 though. 

But, as mentioned above, find the make and model of B2 that works for you. 

Maybe just tell your friend to rent a pair and swap them out if they’re not working.
 

I went up MB in 2019 and rented a pair for the week for the acclimatisation and the climb. I went into a rental shop and told them what my plan was. They’ve gave me a pair of scarpa mont blancs and a pair of Simond crampons and sent me on my merry way and told me I could come back and swap them out for another boot/size if they weren’t working for me.
 

They ended up being fine. Plenty comfy and warm enough. I’m sure there are better boots on the market but my inexperienced feet didn’t know any better and had absolutely no complaints