I would vote for the MX series. I have the MX88, and find it to be silky smooth, relaxing, super damp and yet precise. For reference, my previous ski was a Nordica Hot Rod Nitrous Ti in a 170 - not damp enough. And prior to that it was the famously loved tool of intermediates everywhere in the mid 2000's - the K2 Apache Recon. The MX88 blows them both away in terms of handling, and it's a very smooth relaxing ride.
I would not want to give up any precision and high speed handling through bad conditions for a more "relaxing" ride, whatever that might be.
I'm 35, 6'0 166 lbs, and ski the MX88 in a 178. However I demoed it in a 168 and even though it was 10 cm shorter (too short by most people's judgement for a guy my size) it still had no speed limit. I bought the 178 because I get a great deal on a used pair.
I ski 50 days a year at Mammoth but I wouldn't call myself an expert skier. The MX88 is very relaxing in my opinion because it's so damp. Also it is so rock solid in a turn that it helps YOU relax because you can trust it at any speed. And yet the tails release when you want them to.
You do need to stay in the front seat - but this is the most relaxing kind of skiing anyway. Skiing sloppy in the back seat is what wears one out.
The MX88 is the one ski that honestly made me feel like a better skier from the moment I strapped it on.
It's the one ski I will never sell - except perhaps to get a new one if I ever manage to wear this beast out.
I'll say it again - the MX series will NOT wear you out or beat up your legs if you are even remotely in decent physical shape.
I know it sucks to live where you can't demo a ski - I was lucky because a Mammoth shop started selling them and I could try it. Skiing is believing.