Mostel
4360
5170...
I think the 5960 is more popular because it is an annual calendar, so it's very useful, practical. It's also a bigger thicker watch with a very sporty case. All of this makes the watch more 'wearable' on a so-called everyday basis.
The 5170 was greeted to lukewarm reactions, generally, because it is so very sober looking, drawing on Patek's older, 'dryer' designs... which are not raging with testosterone, like say, at least to ann extent, the 5070, which--in its day--was HUGE in terms of size, and so, considered a very masculine and contemporary choice...
The 5170 is a kind of throwback to more genial, old world type design, IMHO.
Also, it has not been introduced in white metal yet, which will no doubt vastly increase its general appeal.
So there's some reasons, maybe.