I've been playing trombone for about a year now, with my first trombone being a Getzen 747. I went by a music store that trades used instruments in town a couple weeks back and asked about how much their bass trombones were just out of curiosity. I didn't intend to get anything any time soon, but they had this and I was intrigued, especially for the price. I came back another time to try it, but all that was available for me to use as a mouthpiece was the Yamaha 48 I sometimes used for the Getzen. I decided I wanted to try it with an actual bass sized mouthpiece, and I went back when my Bach 2G showed up in the mail. Kind of like with my large tenor, I don't have anything to compare it to but I've been enjoying playing it and I think it will be good for exploring bass a bit. I'll probably play it exclusively for a month or so and then I'll try to work on both again.
The slide at least came from a YBL-322 but I have no idea with the bell/valve section, it's totally unmarked. It's in a dependent set up with the D valve being mounted on the tuning slide for the F attachment. If the YBL-322 came with an unmarked bell, then this was a modification along the way. There is one thing I'm a bit concerned about though. Is it normal for the double valve range to have an extremely different blow? As is, it's very different playing D and Db above the pedals on the F attachment rather than through both valves with the slide in D valve 1st or 2nd.
<Edit: Fixed image - BGuttman>