> Over 85% of our organic search traffic comes from users typing in our brand name - Total Car Check. If they see an advert at the top of the organic search results, for the user, its just a shortcut to get to the site, especially since Google started putting organic search results below the fold in many search results, except it would cost us money to buy a user who was going to find us anyway.

Sure, but you wouldn't want your competitor to effectively rank #1 for your brand. I've always viewed this like an extortion racket.