Hello! First, congrats on your two acceptances!
I can see why this is a difficult decision for you - there are a lot of strengths to each program. I typically find these are very personal decisions but am happy to share my thoughts on some factors you should be thinking about....
1. Career prospects - This depends a lot on your background so far and your future goals. You mention you've worked in engineering and product development, so depending on how much experience you have there, I wonder if the MIT program would be as valuable to you? If you want to go the startup / strategy / VC route, it sounds like the MBA would be more beneficial. But if you see yourself in a more tech-focused role then I would imagine MIT might have better placements. Have you talked to anyone who works for a major tech firm in California? I would be curious to know how they view the two degrees.
2. Alumni network - If you want to end up in California, I know USC has a very impressive network there and a really tight-knit community. The MIT brand will help you too but it may mean you have to make more of the connections on your own on the west coast. I'm sure the school publishes stats on this.
3. School culture - Have you visited both schools or talked to current students? Does one seem to fit better with your priorities and values and interests? The locations are quite different too so don't forget to factor that in.
I think you can't go wrong with either one - they are both excellent programs. I think it's just a matter of deciding which factors are most important to you. Good luck and keep us posted on what you decide!