Brilliant combination with their mute bag,
This review is from: Protec PB309CT Contoured Bass Trombone Pro Pac Case - Black (Electronics)
NB There is now a newer Protec bass case, which seems to be lighter and possibly a bit more stylish. I can't currently find a model number online (May 2015).
Joint review with the mute bag - http://www.amazon.co.uk/Pro-Tec-Bass-Trombone-Mute/dp/B00FMWPJRA/
Before I had this case and bag, I went to band practices with my unnecessarily large and heavy Vincent Bach case and a large (open) bag containing mutes [H&B bucket, rubber plunger, metal cup & straight], music, and trombone and music stands.
Now, the mutes and music go in the mute bag, with spare room for other stuff like sunglasses and lunch. The delicate inside part of the bucket mute is protected, and everything else goes in this case, with the two stands fitting in the outside pocket.
The nice-looking rubber interlocking handles which you may have seen forming the normal hand grip in a Youtube video (and some pics here) turn out to be fiction, but for me that's fine - the velcro-secured "wrapround" you actually get is familiar from previous use of an older Protec tenor case, and I suspect it's more comfortable to hold than the plastic version. Two minor hassles:
1. There's no place in the case designed for a cleaning rod. Best option seems to be a couple of bulldog clips securing it to the top of the slide protector (different to the photo).
2. If you have any added accessory closer to the end of the bell than about one inch forward of the bell/slide locking nut, the storage compartment will get in its way. For me, this means removing the curved rest component of my Rath hand rest - the remainder of it can stay on and just fits.
The optional backpack straps are a good extra if you're likely to be carrying your gear further than a couple of hundred yards.
(The instrument I'm putting in the case is a Bach 50B3O.)
I adapted the storage compartment with a hacksaw so that my hand rest didn't need to be disassembled. Easily done and the remaining blue fabric has stayed in place. Both the black zip grips wore out and are replaced by black bootlaces attached to the loop on the zip itself. Everything else has lasted well. And if you do for the Mick Rath bass mutes, which are LARGE, the bag will take them plus a plunger and bucket.