If you really want flat protection, try the Super Seal sold at John Deere Stores. Big chunks of rubber. The stuff has been on the market since the 60s and works.

Vibrations? Well, it is possible a big wad of the liquid will sit on "one side of the tire" I suppose. I have used tire sealant at Baja and done over 100 in El Diablo dry Lake. No vibrations problems to report.

Good luck.

deekay