campbrs, just on the level of personal preference I also prefer the MK 4 to the MK 4V. But I would prefer the standard CMC amplifier series over the CMC 6xt. Of course that goes with my own preferred methods of recording, so anyone else's mileage may, will, and probably ought to differ.
My favorite cardioids for less-than-ideal acoustics are a pair of CMT 56 three-pattern microphones which I bought in 1973 just a few months before the Colette series was introduced. The MK 4VJ's response is basically similar to that of the cardioid pattern in the MK 6 capsule, so it is in much the same ballpark.
--best regards
P.S.: The attached flyer is from back then, so please don't try to order this microphone from the number shown ...