I am getting into ski mountaineering and have heard that ski mountaineers use shorter ice axes than mountaineers. I'm 5'10" and measure 27 inches from finger tip to ground with ski boots on. What length do you recommend?

Correct length really depends on what you use it for, but you are correct that many ski mountaineers use shorter axes. I use mine for ski mountaineering and have a 50cm and I'm 6'2". It's definitely short, but I'm very happy with it and it works very well for me. There are reasons for this: 1) In ski mountaineering, you're generally only using the axe on the steepest terrain, pitches you can't skin. For steep pitches you can get away with a short shaft. On most terrain, however, you're skinning and even if not you've got your poles. Poles are much nicer for stability than the shaft of an ice axe. In general mountaineering you don't necessarily have poles, so instead you use the shaft of your ice axe. For self arrest a long shaft isn't necessary. 2) Since you don't often use your ice axe and when you do you don't need a long shaft, lighter weight is nice. A shorter ice axe will be significantly lighter, which is nice when the thing is sitting on your pack all day. Lighter ice axes are also a bonus in that you'll be more likely to take it with you even if you don't expect to use it. That extra preparedness has made me happy more than a few times.

I have used the 65 cms length for years and found it to be a little long yet its length feels real secure when you plunge it into the snow. Some people like smaller axes but when its deep and steep longer is better.