I've been loading for 40yrs. I'd really have to think it over because of the investment needed to start today. I've never loaded 9mm. Back in the day loading big bore pistol was a nice savings. If it were me, I'd just have to run the numbers to see if it was worth the investment and time. Also having to dedicate a space for it.
If you want to get the most out of your shooting, this is the route. But these days you may not be able to save money. I just have a Lee turret press. I've loaded pistol and rifle on it. The large African game cartridges are a bit much for it though. The ole tried and true RCBS Rock Chucker is as strong as they get. But you can only use one die at a time. So it is slower. Then you have the Progressive set up. Expensive and you have to maintain it to work correctly.
Personally, if I was to start out reloading from scratch today, I'd probably get a turret press that had removable 'decks', similar to the Dillon and Lee idea. Set the dies up the way you want them, and demount the whole lot when you change to a different caliber.
Of course, that might be because that's a type of press that I don't own, and therefore don't know any better.

