I haven't but I have a half dozen MXL 603 I haven't deployed in years that could use that capsule mod. The k6 mod is also worth my interest.

Yes. I recently had the mod on my Rode NT1A and was amazed by the results! I had put the mic away for over a year because it sounded sibilant on many vocals and brittle on acoustic guitar. After the mod it sounded much more open and captured a lot of detail. It also came alive in the midrange and produced a beautiful punch. I was so delighted with the mod that I sold three of my other mics. I now own a mic that I can put up against anything and it shines. I have a total (including the price of the mic) of $549. into the NT1A and it sounds excellent. The NT1A is also a great mic to mod because it is THE QUIETEST mic on the market with a self noise of only 5db's!

I just had an MXL v67 modded at JJ Audio for $215. I think it sounds very good. I've been comparing it to my AT4033, and right now I'm having a hard time deciding which one I like better on my voice. They both have certain characteristics I like. I haven't tried it on acoustic yet.
I haven't read a single post yet from anyone who was dissatisfied with a mod they got from JJ Audio or Octava Mod.

Excellent. Thank you.

Yes, I had my Oktava 012's modded and love them even more now. I would recommend Michael's work to anyone looking to mod an inexpensive mic.