Ok so I've used it quite a bit now and I've got some feedback thoughts.
1. First up is the whole jimping thing. I can't speak for climbers (nor can I imagine what they would and wouldn't like) but it seems to me the only drawbacks from having jimping on the thumb ramp are 1) potentially damaging your thumb in some kind of extremely hard use. Michael Janich spoke of this about the Yojimbo 2 which was why it also doesn't have thumb jimping. 2) potentially snagging your clothing/pockets when trying to clip the knife back into your pocket. I've had this happen to me but in a casual situation it's not a big deal...maybe it IS big deal when you're hundreds of feet off the ground scaling a mountain...again, I wouldn't know. I think it's important to consider that (much like pretty much every self defense knife ever made) most of these knives will ultimately get used for other uses beyond what the intended design is for, so perhaps adding jimping to the thumb ramp needs to happen because you can pretty much guarantee more people will buy this knife for EDC than for actual rock climbing. I don't think I'd care either way but it will tie into my next concern...
2. I'd rather the scales behind the thumb ramp didn't have jimping at all and were smooth like other models. Example:
That's the RJ, Stretch, and Spyderhawk. A while back in my Caribbean thread I was talking about hot spots when using a knife really hard for extended periods of time (carving/whitling) and I mentioned my interest in maybe making a switch to back locks because the area where the Compression Lock is located is a major hot spot on my palm, compared to the same area on a back lock that is smooth and solid and much easier on your hand. This little bit of jimping that's molded into the handle isn't the end of the world but it does start to wear on your hand after a while. I would rather it was smooth like the Stretch, and then if you add jimping to the thumb ramp you'll still have something that keeps your thumb from slipping forward while still keeping the handle smooth and comfortable.
3. This wee little bit of ricasso that's still sticking out...it's gotta go too. While it's a vast improvement over other back lock designs, it's still a potential snag point. This will depend on what you're cutting, and for a climber I doubt that a rope would make much of a snag there, but for me this design (and this particular knife) can't fully replace my Caribbean unless there is nothing between the handle and the edge that material can snag on. I make a lot of cuts with the heel of the blade, so this is a big deal for me.
4. This is maybe a little nitpicking, but I'd like that extra little bit of blade to be added to completely fill the handle. I know most will say that it's only 1/4 inch or so, but to me that could be another quarter inch of PE at the tip of the blade that could be that much more useful if/when I need PE. This is probably lowest priority of my concerns or wishes, but if we're open to feedback and looking to make changes, this is something I'd change.
Besides that, I'm finding the rest of the handle to be wonderful. It fits my hand perfectly as what would basically be the smallest you could make a handle that gives me a full grip without the need for a choil. Closing it hasn't been an issue at all, in fact if you look at the bottom of the handle there is a contoured area that I'm guessing is there more to smooth out the corner of the handle to give your thumb a straighter/smoother shot at the thumb ramp, but towards the rear of this area there's almost a bit of shoulder to the contouring, and if you feel this spot with your index finger, that's pretty much as far back as you want your finger to be positioned when dropping the blade closed onto your finger. Unless you have very small/thin fingers, that contouring works as an indexing spot and if you just don't move further back from there you shouldn't get cut.
So, how much can FRN molds be changed, and at what cost? Can the scales be extended out just a wee bit more to cover that last bit of ricasso, or can the blade itself be tweaked a bit to seat it further into the handle? I could probably live with the other issues, but that bit of ricasso is what's really standing between me and what could be a perfect design.
Also make a bigger version too. 3.5+ inches cutting edge.