I have an F1. It's a nice blade. The steel is good quality and although, for this reason, it's not as easy to sharpen as other blades I have had, it holds an edge well. Perhaps a little thick on the opposite side of the shaft from the blade (dont know technical term!) for really close carving work, but I like it. The rubber grip is good in the wet.
I have both the leather sheath and the tough plastic one. Both have their advantages and disadvantages. The plastic one is smaller, so catches less on undergrowth, but i've found it's not completely silent as the blade rattles is it a bit. The leather sheath, although larger, is my favourite for this reason.
I've pressed on a couple of popper studs to the back of the belt loop on both, and through the leather case for the fallkniven diamond/ceramic sharpening kit, so that this sits comfortably behind my belt whichever sheath I am using.
Anyway, it's my first serious knife, since the couple I used to own when I was a kid, so I'm much prepared to be educated about better blades.
Hope that helps.
Chris