First things first. Tamiya's spray can primer is lacquer based. Model Master Primer is enamel. With that said, either primer will work fine as an undercoat with acrylics or enamels. I find Tamiya's primer works best for Tamiya's acrylic. In fact, I like Tamiya's primer the best. Unfortunately, it's only available in a spray can and decanting can be a pain at times.
I'm sure people will chime in about weither you should use a primer or not. Try it both ways. Use a primer on some parts and no primer on the other. See which you like. Personally, I like using a primer but you don't have too. If I'm using enamels, I don't always prime. If I'm using acrylics, I always prime. If I'm using Tamiya acrylics, I always use Tamiya's primer.
Good luck,
Jesse