Newbie here. Actually, I joined to talk about my Mcusta folder (MC53D) with damascus blade, cocobolo handles, and pocket clip; so this seems like a good place to start. I got this about 3 days ago, after sending back an Al Mar Hawk that I found impossible to deploy using the thumb stud. My first impression was: Very Pretty Knife! It was a little stiff to deploy, yet smooth. And just just as sharp as everyone says! The blade centering was a bit off. Not rubbing, but off. I decided to lighten up the action by turning the adjusting screw about a quarter turn CCW. It worked. So I turned it another eighth turn, and it got even lighter--but the action changed from smooth to gritty. It stayed that way for a day; then I decided to hold the knife under running water after using it for food prep. After I did this about 3 or 4 times, the grittiness cleared up and once again was smooth as silk. So it was probably just that: grit. maybe even True Grit. The centering, by the way, gets even worse after turning the screw CCW; although not so bad that it rubs. The only other thing is that the pocket clip is much stiffer than it needs to be--it grips very tight, and may prove to be hard on pants pockets. And the adjusting screw sticks out so that it is very hard to slip the knife all the way into place in the pocket for a "low rider" carry; and even harder to deploy from the pocket.
So: it's not perfect, but even so, it's a keeper (for me).