Vantaggi
As a PT they pay you from the beginning, so you have a few months to get your business up and running (at least they did when I was there). This is so good for starting out, and you pay a percentage of the sessions you deliver. Rather than a fixed rent amount so a very good business model for PTs who don't want to have to deliver a large amount of sessions. My Head Coach was also very good, and plenty of training and support was given with 1-1s, sales training and generally a really inspiring atmosphere where they encourage progression. They even asked me if I wanted to become Head Coach myself, but I decided to go out on my own during pandemic.
Svantaggi
They do take a large share of each session that is delivered, so there is a ceiling of what you can earn and you need to work quite hard to get top dollar.