Thus far I've had 7 Rat Cutlery blades, 2x RC'4s, 2x RC6's, 2x Izula and 1 RC-3. I have a forum knife coming in so I can't say how that one will be. Of the 7 blades, most had passable edges. Most of them would scrape hair, but were not hair popping sharp. One of the RC-4's had a wire edge (burr) on it still that could have lead to some performance issues had I not known how to sharpen it. All of them were easy to touch up using a sharpmaker and get to a place where I liked their performance.
A couple of spyderco's I had were sharper out of the box. Many of my custom knives were much sharper than the rat cutlery's on arrival. There have been a few exceptions to that though. I no case did I ever receive a Rat Cutlery knife that I felt was dull. As in dull, I mean the kind of dull where you ask somebody who knows nothing about knives for one of their kitchen knives and you aren't sure whether the edge or spine would be more efficient.
I feel that all of the Rat Cutlery knives I've received so far would have been usable as is from the factory. I also feel that all of the knives I received so far have benefited greatly from sharpening. I prefer a polished edge to the course grinds that ALL (including spyderco, benchmade etc) factory knives seem to come with. So I always take factory edge in stride when I receive a new knife. Invariably, if I like the knife, its gets converted to a convex because I prefer the performance attributes of a convex edge.
No Rat Cutlery will ever likely slice is great as a little Opinel, especially one that has been tweaked to perfection. The RC-3 is a great slicer though. The best of the line IMO if cutting performance and slicing is what you are after. The other knives, including the izula, are designed with tough/robustness part and parcel to their intended use patterns. They are thick and hard to destroy. You can get great edges on them, but they won't slice like that 1/8" thick RC-3 and none will slice like the 0.095" thick opinel.
Anyhow, I firmly believe that learning to sharpen and maintain your knife is part and parcel of learning to use a knife. Many folks like to complain about factory received knives not being as sharp as they like. Personally, I prefer this. It gives me the opportunity to tweak the knife according to how I want to use it. I mean really, if I received an RC-6 with 12 degree angle and delicate edge I'd be a lot less happy than one with a 20 degree angle and robust edge. I can always convert it to the 12 degree in the future but I can't readily take an overly acute edge and make it thick again, short of dulling it flat and resetting the bevel.
There are a few professional sharpeners out there who might be worth while contacting if you want to change the bevel of your knife to something more acute than what it comes with. RichardJ is a good guy here and has a very quick turn around and is pretty cheap in his sharpening fees.
Still, in the end you should learn how to sharpen your knives yourself. Its one of those skillsets you need to know. Just think of it is the same as learning how to notch wood, make deadfall traps, whittle spoons. All those fun things you do with a knife. Lots of people like to shave the hair off their arms with their knives. I really haven't found a practical use for this yet other than to impress your dad or your son or to make your wife's eyes roll upwards.