I used FS-1 for a while in neck position of 25.5" scale Jaguar-style guitar with SDS-1 on the bridge position.
it's quite nice actually if you aren't looking for that sparkle from typical Strat neck pickup.
I started as a humbucker-guy player, so I always get along with more fat, warm neck pickup sounds.
I recently installed the FS-1 in middle of a Strat because a Knoplfer enthusiastic has theory about Knoplfer used FS-1 in middle position (combined with vintage output bridge pickup) for Sultan of Swing.
and now it become my favorite. previously, I rarely used middle pickup alone because I felt it always lack of something. but the FS-1 just doing great for me, it has good roundness of neck position but with enough brightness of bridge position.
I use vintage output pickup for the neck, and the combination is great too, with plenty of quack.
while in the bridge I use SDS-1 (my current favorite bridge pickup), the combination don't give enough quack as the neck-mid combination.
so, the theory about Knoplfer using FS-1 in the middle position for the Sultan might be true. if it combine with vintage output pickup, it gave nice quack sounding.
anyway, you should try the FS-1 in neck, or even the middle, and it might be working for you.