Counter offers never work out in the long term. Now that you've put in your notice, you're no longer seen as loyal. Therefore, had you accepted (bad idea) they would not have kept you around any longer than absolutely necessary.
Even so, trashing your former employer after they offer you more money, however self-serving, is bad business.
I would not hire somebody if I saw them bad mouthing a former employer. What if they don't like my company? When they leave, they're going blast my business for not recognizing their genius/value/divinity earlier? Not good.