Not a pizza nut myself but my late brother used to make his own, right down to the dough. They were fabulous, best pizzas I ever had.
Which brings me to the thought...its one thing to buy a very expensive cooker...you (we) shouldn't perhaps try to rationalise it in 'how many pizzas do I have to cook to make it pay...rather how do I make (or buy) a good enough pizza to really get the best out of the cooker. A Rolls Royce pizza...
I do know someone who has /had a proper cooker...he loved it but conceded they moderately expensive to fire up and you need to keep up with the fuel if you're cooking multiple pizzas.
If you want to make very good pizza buy the book Elements of Pizza by Ken Forkish. He'll teach you how to make a range of styles of pizza that can be cooked in a kitchen oven with a built in grill. Of course, if you have a pizza oven you can use that but it isn't essential.