Luckily, the only "white lie", was that it took about 4 weeks longer for my car to arrive than when I was quoted (no biggie). That was in 2006, so it probably wouldn't be a problem today.
If you're fortunate enough to find CC before you make your purchase, you shouldn't have too many stories.
The threads that I cringe at start out with "I bought this Cobra on a whim and I really don't know what I have."
BTW - The installer that I worked with (Full Throttle in Reno) quoted a flat rate install. No surprises and delivered on time.