As the founder of your company, you must be in love with your brand and inspired by your brand's mission if you have any hope of getting press for your product.
I've gotten more press than any entrepreneur could dream of - certainly more than I deserve - and I've never had a public relations firm working for me.
It's very important as a startup to get early press because, although it may not be a large number of people, having a 'Fast Company' story - some of those people that read it are going to be your next employees and hires, your next investors.