This is not an easy question. It depends on the type of product you're intending to do. I will share my personal view about this...
When the product is a tablet-like and is intended to have 3rd party apps and a reuse Android apps, Android is my the choice; otherwise I'd use Linux. Android will easy some things but it will also be a "fat system" due the number of abstraction layers it has while Linux allows you to make a much lean system which has exactly what you need, no fat.
Without a clear and more deep understanding about your product, experience and wishes it is hard to make a suggestion.