Here are snippets from my reviews last year at SIA regarding the FX85 and FX85HP. I skied a few other Kästles as well, the FX95 and the BMX105, and the common themes were 1. smooth!, 2. quick!!, and 3. Iwanttogoreallyfastonthesethings. Do keep in mind I'm 5'9" 140lb.
First from this tent was the Kästle FX85 (173), which I took to the top of mountain. I found no deep snow, but did manage some minor crud and chalk on a steep pitch or two that I regularly ski. This one was so easy to ski, my initial comment was “it’s like cheating.” Possibly the most fun I’ve had in moguls, ever. Just super quick and slithery, but still held like a champ on the groomed. I suspect it has a speed limit compared to the others, but I didn’t test it.
After lunch I did get on the Kästle FX85HP (173), which was predictably similar to the nonmetal 85, but not as slithery in bumps. It was more zoom-zoom race car quick than jackrabbit quick. I would have liked to ski it next to my MX83. I think some of you who are a little scared off by the seriousness of the MX would really enjoy the FX85.
I am actually seriously considering getting the FX85 for this season: not sure if I want to sell the MX83 or not, but that FX was SO fun in moguls, and we have lots of those around here. MX isn't bad in moguls, but I have to think about it. FX just went. Like I said at first, it felt like cheating. So if you are looking for quick and nimble, I think it will be perfect. I just am not sure about HP or not, since you are bigger than I am.