I bought an F5 sno-pro package but changed the track to 1.0" lug height.
(I didn't want to trail ride with 1.4 + long studs).
I put in 102 1.075 woody's push through studs. I used 1.375 dia. round alum. backers.
I also used the woody's stud guide and I studded the closed window.
I've only been out riding a few times but works really well.
I do not feel the need for 170.