MG21's for me as well. I would be curious to know what I'd think about the Milab supercards given how much I liked the Milab vm44 cards, but I've never run the supercards or even heard a recording with them.
I've owned the AKG ck63s, Gefell m21, MBHO ka500 hypers, Neumann ak50's, and currently own the Beyer mc950's. That's from the list, I've also own the Audix m1290 with hypercard capsules (and card capsules) and have owned the AKG 393 bluelines, Charter Oak m900s, and Busman-modded Aventone ck? hypers (which are supposedly the same as the Busman mics, at least the initial version).
The Gefells to me had the best balance/tone, including an excellent midrange and sweet high end. I've never been a fan of Schoeps mics for recording PA-amplified music, though I admit the mk41 are excellent hypers, and I can see those being the best to many people's ears. Actually, in recent years I have been enjoying the schoeps sound more and more, though I still prefer the DPAs, Milabs, and Gefells to schoeps.
Like many here, I find the AKGs to have a sizzle to them that gets fatiguing. I owned and ran several different versions of AKG small diaphragm mics, including the 460s, 480s, jklabs active box, and JW-mod 460s. I used to love them, but I go back to my old tapes and just don't like them as much as my other mics.
The Neumann ak50 hypers could really be a contender these days for me. They have too much of a low end rolloff that generally makes them a bit thin. But otherwise, they are fantastic and have excellent/even off axis response. They take post processing and EQ really well, and it is quite easy to add back some of the rolled off low end in post. So as is, they are not the best, but with very minimal EQ on the low end, they sound fantastic, and probably are up there with my favorite hypers.
Also, one thing I like about the Gefell m21 hypers is that they sound more natural than most hypers. I came to the conclusion though that this might be because their pattern really lies somewhere between card and hyper, though they are listed as hypers. The Milabs I used to own have a cardioid pattern that lies between card and hyper for many of the frequencies, though it is listed as a cardioid. This is the reason I ultimately got rid of my Gefell m210s -- I didn't find that much difference in pattern compared to my Milabs.
BTW, I now own both the Beyer mc950 hypers and Audix m1290 hypers. Both are excellent sounding hypers to my ear, esp for the money. They definitely aren't Gefell, Neumann, or Schoeps quality, but with a little bit of post-processing tweaking can sound very good and make for excellent hypercard recordings. I like both better than the MBHOs I owned and better than all the cheaper hypers I've owned. I like the Beyer mc950s better than the AKG ck63 hypers, and may even like the Audix m1290hc better than the AKGs. I always thought the Audix m1290s had a similar sound as the AKGs, but they don't seem to have the fatiguing sound I hear in the AKGs.