As a note, I'm a huge fan of Massey tractors! I've looked at several 1700 series tractors and am curious about your comment on not being sold on them yet. IMHO the 1700 series look like an upgraded version of the 1600 series. IMHO the ergonomics/seating position in the MF 1754 series cab is a major improvement in itself over the MF 1643. I ran a MF 1240 for over 10 years and felt that when I went to the MF 1643, after running it for a couple of 100 hours, the quality was just not as good. What are your concerns about the 1700 series, the Tier IV engine? Interested in your opinion. Thanks.
My only previous experience with MF was with a 2007 1540 with FEL and the Powershuttle. That, my friend, was a great little tractor. It wasn't perfect (the ROPS vibrated at certain RPMs and made ear-piercing noises, the headlights were worthless, and it would have been nice if it had more storage and cupholders), but the good far outweighed the bad. That 3 cylinder turbo started instantly in any weather at any temperature, it was the quietest tractor (engine) I ever was around, the Powershuttle was buttery smooth and a huge upgrade over anything we had previously owned, and the loader joystick (floor mount) was much better than what's on the 1600 series (mounted on the fender). I had to sell it just 1.5 years into owning due to the bad economy. Fortunately, finances allowed me to buy this 1643 in 2013 and it's been (mostly) an upgrade over the 1540.
My comments about the 1700 series more or less revolve around the emissions equipment, the newer loaders and wimpy buckets, and also the newer tech in the HST, which I wonder about its reliability. One other observation I've made concerning the 1700s is that to my eyes, they appear to be physically smaller than the line it replaced. Perhaps there is no truth to it, but they really do look smaller across the line.
Not sure why they switched loaders, but they just don't look as attractive or beefy, and the new buckets are an embarrassment.
In the end, I was very happy with the 1540 (and it pained me to have to sell it), am very happy with this 1643, and I hope you find the right tractor for your needs.