Media Buys will NOT be nearly as successful as running campaign on google.
Those google seekers were actively seeking out that product.
Media buys wont be able to give you such a specific target audience.
You will have your ad in front of many different demographics.
I know, you can target specific sites, etc... but will never be as good as google.
What others have mentioned is right too, the roll of the dice will be much larger too.
Good luck, and dont be in a hurry to let that money burn a hole in your pocket.
OC-768