Biggest factor I've seen with any climbing knife was not the deployment or the cut, it was the "now what" afterward. I used a Leatherman CX with a modified tip for a long time, and the rescue one would do well I think. It gives an easy option to both close the blade and clip it back away (though mine lived on a leash anyway). If you ever climb with people below you, dropping a knife is a good way to lose friends. And I've seen so many near misses because the person with the knife didn't have an easy place for it to go, it will find the worst possible place to end up.
I was supplied with a Gerber Zip, it uses a stanley blade, and they are alright, but the sheath leaves a lot to be desired, and forget about accurate or delicate cuts (ever have to clip just a prussic, and not the main?)
I'm not the biggest fan of liner locks, but this is where they tend to shine. Compression locks work too, but there is that added dexterity needed to one-hand them closed. Style of climbing is going to matter some as well, I did a lot of challenge course work and so a cut-away was easily on the menu, where as if you are a lead climber, there is much less chance of having to cut a loaded rope under duress, more like cutting out a really set knot or clearing old tape. So consider that as well. Nothing wrong with having a utility knife if that's all you expect to use it for,
To me, it's retention, closing, cutting, opening, in that priority order. If I was looking to buy a rescue knife today and could pay US retail, I'd be looking at some of the lower-end spyerco liner locks and finding out who had a belt or grinder to do some modifications. I don't think climbers design good knives, and I don't think many knife guys are climbers. If they are, they are also white-water guys who design gear for that, and I don't think they are entirely compatible, but then I'll admit I come at it from a very different point of view than most.
And if anyone thinks I'm being dramatic, its okay, I'll rescue myself thanks