Depends on how a company handles it. First off you should test going from lower price to higher price. Then say you get to $34 dollars and find that $24 did the best, not the $19 or $34. So now all the $19 dollars guys are gonna be happy because they have the lowest price, nobody will mind. If a $34 customer writes in, a company can be either:
A) nice and give him a credit on his account and say, "We have credited your account so that you only paid $24 for this month, to continue getting that price, you'll have to cancel and signup again."
Or a company can be
"Well tough shit, if you want the lower price cancel and signup."
I can tell you if you're nice with using option A, you'll find that the customer will cancel and sign back up. Be nice to the customer and the customers will always come back. Be a asshole like some companies are in option B and you can lose that customer for life.
Another option for a site would be to email all the higher priced customers saying, "We have changed our pricing to a lower monthly price, if you would like to take advantage of this price drop, please cancel and signup again" type of email.
But it's all up to how the company/person wants to try different pricing structures. Another option would be to have two traffic sources, one traffic source gets pricing option A, the other traffic source gets pricing option B.
But you CAN NOT run it only off conversion ratio (like most want to think), you'll want to run it off number of uniques, conversion ratio, GROSS and the most important NET income. But there's ways of doing price testing and making the customers still be happy even tho they paid more by offering them either credit and say giving them the option of the $19.
