I have used the C-4's extensively, and I believe they are excellent SDC's in their price range, very comparable to the Rode NT-5's. The SM81's Moresound has are a studio standard mid-priced mic. I can also tell you that Moresound is a real guy and will not jerk you around on a mic deal. Whichever way you go, you should wind up with a perfectly usable, versatile stereo pair of mics. The C-4's were my main SDC pair for quite a while. They eventually got sold. Today, I do most everything with 3 pairs- AKG C2000B, Oktava MC012, and Neumann KM184's.-Richie