I've not used any of the Soundelux/Bock, but I've sure read a lot of raves and can't remember any complaints.
I hesisitate to say, but I just don't see how the ifet7 can really emulate both the U47fet and the U87 without changing capsules. I realize there's a substantial change in the switchable circuitry, but the capsule is the basis for the sound. So. Is it a K47 clone or a K87 clone, or none of the above? Enquiring minds want to know.
I read a lot about the ifet7 being used on kick drum in place of a fet47, but not a lot about it getting used for vocals. I do read a lot about either the U195, U95, or Elux251 on vocals. With fewer raves on the U95/U99 since the 251 came out.
Mitch Phillips used to swear by the U195, which is why he sold me his 416. He sold the 416 because he wanted one U195 for the home studio, and one for the road. He characterized it as having natural mids with air, and of course the switchable bass boost and cut. Mitch's stuff that I've heard on the air, tho, sounds like it needs a mid-bump, IMHO.
If I were shopping for a 47-type sound today, I'd lean more toward Microtech Gefell with the real M7 or one of the Neumanns with the K47 or K49 capsule. I think that 50 years from now when all those old Gefell PVC diaphragms tighten up like the old U47s of today, those will be considered the classic mic to have. But I haven't tried any Gefell either.
JJ