Rick,
I sell V-Seal as the highest quality penetrating sealer with a 20 year guarantee.
The understanding is that V-Seal becomes part of the substrate (concrete), so in order for it to wear away, the substrate also has to wear away. In 3 years, a customer may see some concrete wear from traffic abrasion on the top surface of the concrete, while still having V-Seals protection beneath the surface. The 3 year maintenance mist is an option, which would be applied to protect the eroded top layer of concrete.
The maintenance mist is applied at 400 sq ft per gallon which reduces the material cost. Since concrete should be cleaned once per year anyway, a maintenance mist for a 1000 sq ft driveway at time of cleaning COULD be sold for around $130.
(Since V-Seal can be applied to a damp surface, within matter of minutes after washing, spray application should take no more than 15 minutes for a 1000 sq ft area. 3 gallons of V-Seal about $60 or whatever contractor and quantity price you may be able to get from your local distributor.)
As Jay Tarantino of V-Seal says: "Bottom line is concrete is concrete and our customers need to understand that and quit asking you to treat it and expect it to act like slate, granite or marble."