Meh, if the stuff is legalized the price will drop through the floor.
It'll be just another crop... stop by your local farm stand... pick up some squash, a couple tomatoes, and a z of da dank...
I hate to say that commercial growers would pretty much either be forced to compete with 'legitimate' farmers, or go outta business.
It's one of the ironies of cannabis' current legal status. Only the cashcroppers really benefit from the laws as they stand now. It's fooked.