Replying to Armada JJ sizing predictability

Hi guys

I've just done all the shops here in St Anton, Austria and so far only found one shop that has Armada JJ's. Sadly, they only have a 175 in rental, and only the AK JJ for sale.

I am demoing the for sure (as well as 180 Line SFBs) but I am wondering if I can ever buy the right size without having tried that exact size. How much will it change? I've never bought a ski of the sort before.

I am about 184cm tall (just over 6ft) and weigh in at roughly 82kg (about 180 lbs) so a fairly big guy, the 175 will almost certainly be too small but it's going to be a tough call deciding between an 185 and the massive (and stiffer/wider) 195 AK JJ I think...