I recently bought this case for my King 3BF which is on the smaller side. The velcro strap that secures the horn inside the case is probably designed for bigger trombones, but after adding an extra set of self-adhesive velcro strips (3€ at a fabric store), it fits super nice and snug!
The trombone compartment itself is also long enough to fit my horn even with the tuning slide way out, something the original case did not.
The lidded accessory compartments are pretty spacious, but the one closest to the tuning slide section is just a little too shallow to fit my (Bach 5G) mouthpiece. Not that it matters, as the other compartment is much deeper and can fit several mouthpieces and maintenance products without any problems.
Other than that, the case is super light, easy to carry and has a very comfortable handle. The color is very vibrant, but it doesn't take too much to make small scuff marks in the lacquer.
As for protective qualities, I haven't used the case for very long, but it has already protected my horn from any damage when I tripped while carrying it.
All in all a great case for anyone looking for something a little lighter or more ergonomical, while still wanting to keep their horn safe.
