I've seen some people say that you shouldn't mix brands when dealing with midside, but I've also seen people say it doesn't matter.
I just bought an MKH30 and am looking to pick up a hyper/super cardioid for the mid.
Logic would say to get the Senn 8050, but the Schoeps CMC641 is such a standard for booming (I also want to use the it for dialogue), that I'd love to pick it up and use it with the MKH30.
The 8050 is even a bit different from the MKH50, so would it really be that much worse of an idea to go for the CMC641.
I rented both the 8050 and the CMC641, and liked both equally, but people rave about the Schoeps sound... and I could stomach the 500 dollars difference if it would sound great with the MKH30.