I am sure other, more experienced, sharpeners will chime in with their own opinions. But for me, it really depends on your particular needs, what you are sharpening, what you are looking for, and what you like to work with. My two favorite "brands", as a group of stones, are Naniwa Chosera and Shapton Pro. Shapton pro tends to be very hard, for me, has little feedback, and can be used splash and go. The chosera stones, on the other hand, tend to have a buttery feel, provide great feedback, but do need a little soaking before use.
I am neglecting to mention any of the single stones I like best, a few of the Gesshin stones (found at JKI), The JNS 1k (my favorite 1k stone), and lets not forget the great low grit beston stones.
Overall, depending on your needs, any or all of the above would work out well for you.
Regards,
Chris