An MBA is not a necessity to run a business well. After having worked for a couple of years before I did my MBA, I realised that I could identify with a lot of concepts being taught in class and I could now give a name to each of those experiences/behaviours which means what I was essentially doing was learning from other people’s experiences documented in the form of principles. As mentioned in a previous answer, if this knowledge is what you seek, you can always find enough literature online and can go ahead and go through the typical books that are used by MBA courses. The real value from an MBA comes from the network you build since that is what you leverage on throughout your career. This is the reason why the utility of an MBA is directly proportional to the kind of B-school you go to.
While an MBA degree is a good backup in case your business does not do well and you end up taking up a corporate job, its also a great way to change careers in case you want to pursue something completely different from what you have been doing till now. I would suggest running your business and focussing on it and hire MBAs instead of pursuing one. In case things don’t work out the way you expected them to be, you can always go to B-school and will be valued for the rich entrepreneurial experience 🙂