There has been a huge amount of hype and media about Profoto's revolutionary lighting solution the B1. Pitched as not a mono-light and not a speed-light, but somewhere in between the two. It's certainly unique in the market place at the moment and I'm sure it will soon have a lot of imitators as other lighting manufacturers join the party. But how do they hold up in a real world expedition? We recently took 2 of them on a 3 week trip to the forbidden Kingdom of Lo Manthang in Upper Mustang to find out!