I started split. Switched to three under, and was able to see an immediate improvement as it brought the arrow closer to my eye. But a couple of years later I had become more instinctive. The arrow in the sight picture wasn't as important. At that point, being able to have more control over the arrow in awkward shooting positions that is afforded with split finger made me switch back. After a couple of weeks of hitting too high, my brain adjusted and I was just as accurate. I've also been teaching people introductory archery (Girl Scouts mainly.) Many have an easier time with three under, again because of the proximity to the eye I think. It also allows you to string walk if you ever want to go that way. And there are a lot of very accomplished hunters on this forum to testify that three under works well for them years down the road too.
But I think after you get comfortable with your point of aim, instinctive shooting, etc, it doesn't matter much. Your brain compensates either way. When it comes to tree stand shooting, you should be tilting at the waist and your sight picture should be identical to shooting from the ground, right? Otherwise your form is more of a problem than your sight picture. And for me, split finger allows a little more control over the arrow when quickly trying to nock an arrow hunting or shoot with some reverse cant, etc. Not to mention most bows are built for split and therefore you have more options when sucumbing to the bow aquisition disease many of us suffer from.
As for noise and the bow -- you'll want to move your nocking point up a little. I've re-tillered bows and made some myself specifically for 3under. I think they can be just as quiet that way. But in general, most are built for split and when shooting these they will be noisier when shooting three under. That noise and vibration is a function of more energy going into the bow (due to messed up limb timing) and not the arrow. This may theoretically shorten the life; but I think in the real world you'd be hard pressed to ever see the reality of that theory.
Now, I've expounded a lot here because I've thought about it alot in my own switch back and forth and bow making experiments. But I'm no expert, so take it all with a grain a salt and a healthy shot of tequilla. Try three under. If you seem to group better that way, give it a shot for awhile. You can always go back.