Been wanting to fill in this thread with details of my testing day a couple of weeks ago on the 183cm AX's. Skied Loon mtn in NH on some blue trails, winding cruisers. They were pretty well scraped off, with one trail with better snow for comparison purposes. I wanted to be on hard pack so it would be similar to my first day of testing with bindings at +2 and dull tips.
Sharpened tips this day (made a huge difference in tip grip, as you would expect).
+4 cm mount: This was my first run of the day and wanted to just go all the way forward and see what it felt like. Well, I though someone changed my skis on me. They turned very quick, made almost short radius turns, had very good grip, and could feel the whole edge engage including the tip. The combo of mount point and sharp tip really got rid of the GS turn feel of my first day out. At speed, the skis felt good, but maybe a little nervous feeling coming from the tip. I mentally felt too far forward on the skis, but they really skied fine, it was mostly in my mind. The heavy tip feel from the first day was completely gone, the skis didn't feel light, but they felt normal for a powerful carver. They are a combination of burly and cushioney. They kind of absorb everything, but will give back as much as you want depending on how hard you push them. I will need to get used to how they respond, as one turn they popped me about a foot off the snow exiting a turn. Another turn they did not. That is me needing to get used to the timing of releasing them and shifting my weight for and aft on them. These skis have significant tip rocker for a carving ski, and with me being that far forward, I could feel the tip being more engaged in the snow. I think the major consequence is a slightly nervous tip at high speeds. The ski did not feel out of balance or loose grip at the tip or the tail. Being that far forward didn't seem to bother the ski at all. That is pretty surprising and shows how versatile the ski really is. I made 2-3 runs at each mount point.
+2 cm mount: A bit longer turn radius, not quite as quick coming around, normal feeling tip (not heavy), and most everything else the same as +4. The too forward feeling went away and the tips were less nervous at speed. I felt pretty comfortable at this setting and started to push the ski more and relax on them a bit more. I was impressed the ski tips still engaged and pulled the ski into and around pretty well. This is when I realized sharpening the tip made quite a difference and the binding mount was more about how much force do you want on the tip to drive it around quicker and into a shorter turn. I felt good at this mount point and decided to set it here at the end of the day.
0 cm mount (factory line): They were still feeling very good at this position. The ski began to feel more GS turn shape (longer radius than +2) and I had to put more work in (bend it) to get it to do a med-short radius turn. I could sense just a very slight heavy feeling from the tip, mostly because of the first test day with a dull tip sensitized me to this. The nervous tip feeling at speed went away completely and the ski felt like it could be a high speed rocket. I can see how the factory decided to make this the recommended mount point. It gives the best balance of high speed cruising versus turn quickness and turn radius. I could have gone back 1 cm more on mount point, but I didn't bother based on what I was feeling. If you want to do a lot of high speed cruising and don't mind a little more work to get a quick turn, this would be the mount position I would choose.
All three mount locations feel good on this ski. I feels balanced everywhere and seems to just trade off turn radius and quickness for a little high speed stability. Basically if you want the ski to turn a little quicker and smaller radius, just move the binding forward. Unless you ski really, really fast, you won't be giving anything up. This is quite different than a lot of other skis I have experimented with. Typically they have a definite "sweet spot" that feels the most balanced and gives the best response while turning. I have had skis that their tips and tails wash out in turns as I move the bindings forward and back. Not the AX. It seems to have a wide range of mount position that the ski works well for.
I also made some runs on a steep black diamond trail with pretty good snow at all three positions. This is where I felt the nervousness at speed the most, especially on rough surfaces. I attribute it to the tip rocker and how much weight was on the tip of the ski. I chose +2 as my preferred mounting. I skied at that setting another day at Stratton, which has wide, smooth, and fast groomers. After that day I thought I might fine tune a bit by trying +1, +1.5, +2 . For this ski and a "clyde" skier I think that is the preferred range. For lighter skiers, I would say +2 to +2.5 as the best range. Check your tip bevels and sharpness, especially make sure the sharp edge extends forward of the tip contact point by a couple of inches. Lastly, I like the 0.5/3.0 bevels on my skis, but I can see why the factory makes the ski more forgiving by using a 1.3/2.0 tune. 2.0 will give plenty of grip for non-heavy weights, and 1.3 will make the ski more forgiving and less reactive to initial edging, hence easier to relax on.