draggat, etc;
I've circled the sun a few more times than your f-i-l - and I have lost some feeling in my fingertips - and strength in my hands too. Blame it on CTS and a neck injury, among other things. I added Case knives to my collection a few years ago - and no more - my thumbnails aren't strong enough for openning some - like my Seahorse Whittlers - without break-in. I much prefer German-made 'classic' Bokers - Tree Brand, for example. I feel they are excellent buys in 'traditional' slipjoint knives (Stockman, Trapper, Canoe, etc.). I have a small collection of them... and SAK's... which I hardly ever carry. I can be found most days with a Benchmade, Buck, CR, Kershaw/ZT, or Spyderco 'modern' folder in my pocket. My beloved Buck 110 is a great knife - I even have Buck Custom Shop examples - but many of them are difficult to close, so I am selective as to which ones I can carry. I have never had trouble opening or closing a Benchmade, whether an AXIS lock, liner/frame lock, or lockback. I am not fond of assisted knives - or full auto's, either. I also don't care for pocket clips as I prefer to carry my pocket knives 'in my pocket'. My latest pair - a ZT-0566 and ZT-0770CF - had both their assist springs and clips removed after arriving home. They are great knives - now - to me (YMMV). As to Syderco, I cannot say enough about the utility of my latest Native series - the Native5 in G10 (C41G5). It weighs an ounce more than the staked FRN handled version with it's hollow-ground S30V blade (C41BK) like I carried for years, but you get a screwed on G10 scales over skeletonized SS liners/full flat ground S35VN bladed knife. Both have sturdy yet easy to close lockback actions.
Now, if you have a dealer with Benchmades, give both the AXIS lock and lockback 'Bone Collector' series folders a look. The small Bone Collector AXIS lock, 15030 series, is a handy size - and available in walnut wood or G10 scales. All have D2 blades. If you think he may want a smaller, aka 'Gent's' knife, consider the 482 Megumi in CF & Cocobolo wood with a 2.48" x 0.11" blade of S30V - with a push-button liner lock. It looks and functions great - especially nice as a Sunday knife! I have what I've suggested - and you should be able to secure them for <$200/each.
If money weren't an object, I'd look at getting him perfection - a Ti frame-lock with an S35VN blade - a small CR Sebenza. Even the 'plain' variant won't leave much left of four Benjamins... but what a perfect, if God-awfully plain, knife!
Stainz
PS Have you thought about gifting him a gift card to a local store and going with him to peruse their stock? My son did that to me some years ago to a local shop... it started this knife-collecting madness!