Hey DC,
The Belstaff Mojave (or brooklands as it's officially named) is 100% waterproof. It's got a waterproof membrane behind the wax cotton layer, and the wax cotton alone will allow 99% of the water to run straight off anyways as that creates a waterproof barrier.
It sounds daft, but we've never had a waterproofing issue with a Belstaff jacket. Bearing in mind, it'll probably take a year for you to get enough water through the wax cotton layer... so by that time it's out of warranty anyways. Even still - we've never had anyone mention to us their Belstaff isn't waterproof. But if they did Belstaff are amazing with any warranties, they'll sort it out sometimes 2-3 years after it's run out of it's original Warranty.
The Brooklands jacket, is now discontinued though - it's been in the range since Belstaff made a come back in the early 2000's. They've changed it numerous times over the years to make it better and better so the latest one is the most technical version. The jacket being discontinued is what's brought the price rocketing down. We're doing a fair amount off.
They are quite short though yes, I personally would absolutely love one... but I have a long Torso which means I just can't wear one without it riding up too high on me, but if they do fit, they're one of the nicest, if not the nicest motorcycle jacket on the market today. I believe around 50% of our customers use them for casual purposes only. They're so much cheaper than the fashion range and the quality is twice as good... amazing what people will pay for sometimes!
Give us a shout if you'd like one
Know everything about them!