Bear,

If you post this question at Rodbuilder.org you will get some insight from some of the worlds finest custom rod builders.

If you expect to see any inovation grip wise on medium to high end fly rods from the major manufacturers, it's not likely for a long while (they are still using WIRE guides, for cheaps sake!).

But there are nice alternatives out there.

Some are ultilitarian, some are incredible works of art.

I can tell you from experience that closed cell foam made into rings and glued up into a grip does NOT work.

Good Luck!

Buddy