My mum had the new version for her last horse, although it's currently surplus to requirements and needing to be sold.
I dont know about the old versions so couldn't advise of any difference there. However new winters in general have a new fitting system. This one of mums has adjustability in the panels as well as the head plate so if you have a good fitter the fit can be fine tuned.
Mums old horse started life very wonky so this system definitely helped as he straightened and the saddle could be adjusted slightly during the regular changes.
However she paid £1200 new for it about 2yrs ago and I would have thought that there were "better" saddles out there for that price than a new synthetic?
I don’t know about the technicalities but, from my expreience, they’re very different in terms of comfort!
I had one of the original synthetic ones which I loved. OH bought a new leather version last year and it’s absolutely awful to ride in. (Although OH loves it!) It feels like riding on a block of wood. I have since read that the new model tends to be uncomfortable for lots of women so this might have some truth. (OH found his second hand having only been used a handful of times; perhaps this was why).
Also, according to the saddle fitter, there’s an anomaly with the gullet fit in the new ones as the gullet sits onto a recess which tends to make them fit wider than the same gullet in the old version would.
Thank you for your replies. I'm considering a 16.5" for a short backed cob with a bit of wither who measures in at XW so actually the fact that it fits wider is actually a bonus, as are the flatter panels. I've heard that the panels aren't quite as long in the newer models than the older ones were, which would also help us... Worth a try anyway!