Top Liner Lock Hedgehog (S35VN Blade & Aluminum Handle) - A1304 by Vosteed

Out of the 3 you're looking at currently, I think the Parallel and Bel Air are the better bangs for your buck. Which is better just depends on what you're looking for. If you want ULTRA thin, the Parallel will be your huckleberry. Absolutely disappears in the pocket, though over extended use the thinness might dig into your hand a bit. The Bel Air is similar in overall size and shape, but noticably thicker in the handle which is a good thing for comfort. As far as the Bugout, not a bad knife but IMO the Bel Air is twice the knife for noticably less cost. And, I generally avoid Benchmade and Spyderco knives from Amazon due to the prevalence of fakes/counterfeits. Unless you need the ultra light weight of it, the only time I really recommend it is if you want to tinker and take advantage of the aftermarket which is massive. If you don't mind branching out from crossbar locks, I just got a Vosteed Psyop 299 and am a big fan. I got the titanium/Ironwood one which isn't on Amazon currently, but they have several of the micarta models available. The Porcupine Ti Slim from them is another interesting option. There's also a few of the premium Kizer Drop Bears that fall in the same price range. Also, it's a bit different, but the Vosteed Hedgehog is an awesome knife.