I started gas boat racing with a gas cat. However, all the boats are equally prone to flipping. I would find what the other boaters in your area run and start with that class. You will get frustrated with many problems that they have already solved. It takes a year or so to get the experience you need to race. I would also consider buying a used bost. Even if everything isn't the latest and best, it will be an inexpensive place to start. Once you get some experience and see what you would like to run, you can buy new equipment.
Lohring Miller