The F1 is basically a Loveless style dropped point hunter. That is NOT a bad thing. It is a very, very useful overall knife, very versatile. And it would work just fine for self defense, God forbid, since it has a guard (a bit small however) and a rather good, tacky grip in "Thermorun Elastomer"... a rubberish compound. You may find the rubber hangs up a bit on a draw from concealment compared with Nimravus which looks like it uses G-10. VG-10 should be very similar to ATS-34 in performance. It has a hidden tang (grip covers completely), but it is pretty full, and the tang metal is visible on the butt of the rubber handle, so you can carefully pound things with the metal if you needed to in a pinch. Strong knife. My cousin (big deer, quail, and turkey hunter) liked it so much I gave him mine as a gift. That reminds me... I don't own one anymore...easy enough to remedy.
The Seal Pup looks good, but 440A is not a steel known for edge holding, in fact, is is fairly mediocre to be kind. The carbon content is low, .6% to .8%, compared with the much better edge holding 440C (.95% to 1.2%). That means you can't harden 440A very well. 440A is a cheaper steel, easier to form blades in mfg operations, with punch dies, etc. 440A will be tougher since it can not be hardened as high. You trade toughness (chopping, prying) for edge holding. SOG has taken a long time to get away from 440A in their product line. It takes an overhaul/augmentation of production facilities. They are starting to move finally. I sold all of my SOG stuff (Tigershark, Tech II Bowie) after I witness edge retention.
The Nimravus comes in 4.5" and 3.65" blades. The 4.5" blade is illegal for self defense (outside law enforcement) in most states I believe, with laws varying from 4" to 3.5" to 3", depending on state. So if that is an intended task, save yourself the legal hassle and buy the 3.65". I like the sort of drop point, sort of spear point blade grind. Looks very utilitarian (I mean it looks like it wouldn't piss me off if I cleaned a deer, cut open boxes, cut stuff in backyard, etc). That is important. I think self defense optimized products are oversold, and overhyped, so for me, since 99.99% of what I do is use the blade to cut everything BUT people, I like a blend of utility and self defense traits. IMHO thing.