Hi! At the time of my purchase, a couple of years ago, there were no differences between the models, beside the one correctly pointed out by Larcivs Lepidvs. The tang its exposed in both versions in the same way.
I have used this knife quite much, but much less than the F1

. Overall its a good performer, can be a beater. The tip is really very strong :thumbup:. The overall dimensions and geometry make this a good outdoor buddy for normal camping and hiking tasks. The sheath it's very well done.
The only thing I really had problems with it was the "obtuse" angle. EKA claims its 20°, but, to me (I havent measured it), seemed at least 30°. I had to reprofile the edge because it was very hard for me to use it as a decent slicer, both for wood carving and whittling (e.g. feather sticks) and food preparation. This done, it is a very good tool. The edge retention is decent but not great, and, specially when I process hard wood, it lose its edge relatively soon. Easy to sharpen it back in the field with a DC4, takes a good working edge. At home, with KAI stones, it takes a shaving sharp edge. Here you get some pics, for reference, from last year (I think), when I built up a Swedish torch my way

. Overall, if you ask me, I can recommend it. Don't expect miracle performances out of it, though

.
Hope it can help!