I've always used Galfer or Goodrich with good results. I have one of those brands on the Versys, I forget which one, LOL, I think Galfer. I put on Vesrah RJL pads. Those two changes improved the braking.
I found the Vesrah RJL pads on Street and Competition. They didn't list them directly, but I believe they are the ones that fit the Suzuki SV650. Look for the 99- model (I think, check others if Versys isn't listed), click, and it lists all the other bikes the pads are compatible with, you'll find the Versys listed. If it's not the 99-whatever year, check the next year range up. It's been awhile since I bought them.