Yes, I have.
I've tried full ports, full grommet, grommet@12 and ports at 3&9 and ports at 12 and grommets @ 3&9.
Full grommets- Really shrinks the sweetspot. Racquet feels stiffer. Less spin production. More of a traditional feel. Not that oversize forgiveness that full ports offer.
Ports @ 3&9, grommets @ 12- Strange brew. Prefer full ports or full grommets to this set-up.
Ports@12 and grommets @ 3&9- The best hybrid set-up. Spin production is great, nothing like full ports but also has a more traditional (tighter) feel to the string bed.
Fire away any questions you might have.
"how many times??!?"