So far, I've installed the new 705's on approximately 60 cars, plus four locomotives. (two blackstone C19's, two Grandt Line original 23-ton boxcabs.) I plan to equip my entire fleet, and will sell off about 95% of my 714's.
Given a choice, I'd definitely prefer any new RTR equipment ship with the 705's vs any other option (including sergeants).
The 705 couples easily with the 714 and N scale versions both, on straight and level track.
On curves, there's a bit more manual alignment needed to get them to engage.
I only have a single sergent-equipped car, but the 705's couple easily with that as well.