Please take the time to see a fitter before you order anything! Titleist Thursdays are free and offer you the chance to work with a qualified fitter to make sure you get the best clubs for your game.

You really need to get to a fitting on a range and see if you do best with either the AP3 or AP2. Let the fitter work with you on that shaft and others to optimize the equipment to you. Might as well get the best value out of a grand investment.

Get a professional fitting, whether from a local pro, or through a Titleist Thursday event, if one is in your area.

I did a fitting a couple of months ago for 718s, coming from 712 AP1s, the latter having the NS Pro 105T stiff in them. Through trying a few different club heads and seeing the performance, the decision was to stay with AP1s, but with PX 6.5s.

Try 'em out, see what works. Let the numbers decide your clubhead and shaft choice.

David. You could go that route but why take a chance and listen to us? I would (and did) schedule a proper fitting through Titleist Thursdays. Not only will it help you decide between AP1, AP2, or even AP3, it will show you numbers for the best shaft option. Don't take a risk, get professionally fit.

Go to a Titleist fitter and try several shafts. Your ball flight numbers will determine what is the best shaft for you....

I changed from 714 AP1 to 716 AP2 and I feel that I've made the right choice.
You will of course sacrifice distance as the the AP1's are two to three degrees stronger. The AP2's IMO are far superior what you sacrifice in distance you will gain in work ability and feel. I'm sure you will have the same situation with the 718's.
As for the shafts I'm not familiar with NS 880 AMC. Mine are dynamic gold AMT reg flex. Go and hit them first then make your mind up.

The NS 880 AMC is a higher Spin/Launch shaft than the 105T- the 880 shaft weigh is 97 - 107 grams while the 105T is a constant weight at 113 grams. A club fitting is the best way to compare there shafts- a recommendation without knowing your swing, the performance of your current shaft etc. should not be made.