I replaced my bars with Renthal fatbars for ergonomic reasons and I am chuffed with the results. I paid 85 pounds for the bars which was a lot but it was a total cure. I didn't drill the bars at all, I rewound my heated grips so the lead came off the inboard end of the grip, made up some inserts from ally bar for the end weights and glued them in. Stunning job. The bars are oversize so I had to buy Reikon adaptors and these sit on top of Migsel risers all of this on an 1100GS from '99. The vibration issue is non-existent to me, I can't feel any difference at all. Most of the vibes on my bike come from the drive train up through the seat of my pants anyway.
What I lost in money I got back tenfold in comfort value and usability.