What is the future potential of the business?

Do you personally have what it takes to lead it to that potential?

Are you a starter, who gets bored after the technically hard parts are solved?

Would the proceeds, if invested in a combination of bonds and dividend bearing stocks, provide an annual income that you could live on in a modest manner for the rest of your life? By this I don't mean SF, NY or London but a nice location with a more modest cost of living.

If you are getting bored and the exit would provide you a base salary for the rest of your life so that you could explore other new ventures ... I would take the exit.

In the end no one but you can really decide but these are some of the questions I would ask myself.