The obvious pro is giving people making below $15 an hour more money in their pocket.
The cons are not just the potential for increased prices (which depending on several other factors could cause these individuals to be in the exact same situation if prices increase by the same % of their salary increase) - the other negative is for these companies looking for alternatives to hiring people. For example as our local salaries increase - some companies outsource overseas for cheaper salaries. This has happened at my company. Now it is worth the additional investment to go overseas, train and start an operation there where the salaries and benefits are significantly lower.
The other alternative is technology. Is it now for cost effective to replace people with machines? As salaries increase resulting in increased costs to the employers -- other alternatives may become cheaper resulting in less jobs.
Now I don't know if this increase in minimum would result in that - as I don't know the cost of these alternatives in comparison.
But those are some of the potential cons. Increased prices to the consumers and loss of jobs.