It may come down to money, but the 2017 has non-performance improvements over the 2016 -- it has Sync 3 & Car Play which is the next generation infotainment system. It's very good, fast, responsive, etc. The older models don't have it. And well the 2016/2017 have improved exterior aesthetics which make it look more like a Land Rover. The 2016 might not have LED fog lights, and other minor differences.
Obviously, if you go 2017, you are buying new, and that's what I did 6 weeks ago. Also Smoked Quartz is a new color for MY17 -- it's a super dark gray, basically 90% black. That's what I got. Looks like crap on the website config. Have to see it in person.
I would not consider any of the older models, unless saving a bunch of money is a priority for you. I have no intention of tuning mine because it'll invalidate parts of the warranty should something go wrong and Ford only have average reliability. Going 0-60 in 6 seconds is pretty powerful already, and it feels pretty special in a 5000 lb car. Amazing engine note, and in my opinion, best bang for the buck for a performance based 7-seater, family hauler.
All-in-all, very happy with mine and haven't experienced any issues. Although I did have a minor alignment issue in my rear hatch but it hasn't happened since I took it in to get looked at. And there is a known issue with minor throttle oscillation if you start the car after it's been sitting for 30-60 minutes. Seems to be an oxygen sensor condensation issue, and hitting the gas burns it off, but under light throttle, the car can lurch weirdly for a couple seconds. Doesn't matter if you are going forwards or backwards.
Things I dislike most about this car:
- The way the 3rd row seats deploy and stow. Nice that they are powered, but whenever you switch modes, you have to move everything. Anything in the well has to be cleared out before you can stow them.
- I regret not getting bucket seats -- the standard 3-seater bench doesn't adjust forwards or backwards, but if you get the bucket seats, you have more flexibility, but lose one seat. The bench seat is a bit of a pain to fold.
- 6 speed transmission is a little crude. I like Audis that make use of the brilliant ZF-8 transmission, which always has you in the correct gear. I've gotten used to the Ford, but it's a weak point. Sometimes when you hit the gas and it down-shifts, you get too much power and the car lurches, and other times it lags before it realizes you want to go. It lacks refinement. But again, once you get used to it, you're better able to anticipate it.
- Roof rack has really low weight limits (45lbs with sunroof, 100lbs without). My assumption is that it's a center of gravity thing rather than a structural integrity issue.
- Weak seat backings for 2nd/3rd row. Don't let kids crawl around in the back to fetch things, and don't throw winter tires in there -- be delicate while loading/unloading.