I hate to be the party pooper, but I'd would tell you to first get traction on your product, and then only quit your job if you feel you have no other choice than quit your job to do this full time.

Also be careful about your contract with your employer, making sure you're not overstepping boundaries that you have signed on. Some employers will take anything you've developped outside of work as their own IP, there are ways around it of course.