TubeNet

I'm thinking about buying an F tuba at some point down the road. What horns would you all recommend? What should I avoid? What have your experiences been with F tubas?

I'm no expert. I'm no professional.

The B&S F rotary F tuba is pretty much the industry standard F tuba.
Buy a second hand one and learn to play it. It could be the only F tuba you ever need, or it may teach you what you'd really like in an F tuba.

There are various model names and numbers, but they're all pretty similar: Symphonie, Perantucci Model, PT-10, PT-15, PT-16, JBL Classics, 3099, 3100, 5099, 5100. John Packer (JP) evidently makes a very high quality copy of a PT-15 at a reasonable cost.

F tubas are good for a few reasons:

There are many good ones, none are so expensive as to be a terrible buy, they are not difficult to sell, and over a long period of time they hold up well price wise.

Used ones in great shape are easy to find.

I learned to play one on a borrowed horn, and coming from BBb it was easy.