I had EBMM Group V flats on my SR5 for about 2 years. I really enjoyed it, but then I switched to a cover band that plays a wide variety, so I switched to cobalts. MAN! they sound great. The flats are almost impossible to bend, and are extremely stiff on my plucking hand as well.
When I got my Honey Roasted Bongo I had flats waiting for it.
I used them in the studio with great results but eventually went to Cobalts on that one.
I put the flats on my Neptune Blue fretless when it came in.
It's flats all the way on the fretless and now I'm waiting for the Cobalt flats.