I can tell you, having just gone through the GEICO quote system myself, that this guy is full of $*%^.
I lied, saying I was 19, single, no accidents/tickets, and selected top of the line coverage for every single option for a 2005 Mustang GT daily driver...
...and got $4,088.70 for my 6 month quote.
Realize that this is with some pretty outrageous options, like $100k/$300k bodily injury, $100k/$300k uninsured, $100 deductibles on collision and comprehensive, ERS, rental reimbursement, and breakdown insurance.
If this guy bothered to get a quote for a real person and a realistic policy, it would be much lower. With my fictional 19 year-old male single, and exact middle-of-the-road policy, I was quoted $2906.40 for 6 months. Full coverage with minimal options resulted in a quote of $2578.70, which is still high, but... I'm 25, and paying $400/6 months for my '95. Big bleepin deal.
EDITED:
Going through GEICO, entering my real info under a fake ID, I got a quote of $519.90/6 months for full coverage, minimal options. Whee.