Plugin will store your “price” as float so any time you will change desire number format there will be no reformatting problems.
Best column type in database for “price” related fields is decimal. As WordPress keep meta as type “text” I can only cast it to float. Keep it in mind.
Field validation is “live” thanks to https://github.com/teamdf/jquery-number.
When you use get_field function you will get preformatted number based on your settings.