I love my Karma mics-- I have two K-6's, a K-58 multipattern tube, and just got a K-35 multipattern FET yesterday. I think they lost some momentum because they ran out of stock of basically all of the mics they carried and from their website and newsletter, it sounded like a shipment got stuck in customs. That happened right after they got a very positive review on the K-35 in TapeOp, and there was some buzz, but nobody could buy any.
The K-6's are great phantom powered ribbons that I use on acoustic and electric guitars and vocals (haven't tried drums, which is the reason I bought two), and the K-58 sounds great on vocals and acoustic guitar. I swapped out the stock 12ax7 for a 6072a tube on the advice of kidvybes and ljmaxx and it improved the sound significantly. I haven't gotten a chance to test out the K-35 yet, other than to make sure it worked.