Great point Marcus - I plan on trying higher sizes than I originally demoed exactly in the range you were talking about. High 170's low 180's. I think I have been skiing to short with my size and it is definitely affecting my performance on crud and soft snow.
JayTierney mentioned it in the very first reply, but if you're going to be demoing again, I'd make sure to demo different sizes as well. You aren't a small guy and you may find that you're comfortable with something in the low 180s, particularly if the ski is rockered or has much of a twin tip. I'm a bit taller but notably lighter than you and my twin-tipped Mojo 90s feel good at 186. For non-groomer skiing, I wouldn't want to go much shorter. On the other hand, my brother is very close to your size and skis on sticks close to those of your current size, so it's all personal preference. Try some different sizes and see what you think. If you're on the fence now, go for the longer size you're comfortable with. You'll likely be happier with it as you improve.