I just got one of the G clarinets with Boehm system keywork, a very new and exciting product from the same Chinese maker as my favorite C clarinets. They have been selling Albert system G clarinets for some time, so-called Turkish clarinets, so they have the acoustics worked out. It's a practical key to play in because the low register is in C. Fine for an improviser and by-ear player like me.
BUT ... it's not a mature product. They made incredible mistakes. The bell is WAY too short. It has serious keywork and ergonomic issues*, and about 8 holes to retune (worse than the C clarinet). It's been a major hacking project, but I got it working with a few days of serious shop work. I suspect it will be improved over the next couple years, as the C was. Simply said, they are dumping their bad prototypes on eBay.
However, having extended the bell with electrical tape and gotten lucky with a mouthpiece, I have myself a fine instrument! The tone is gorgeous, but ONLY with one particular Chinese mouthpiece. Any of my favorite MPs or any others I tried are either resistant or just sound mediocre. I still have more to learn. If there is interest in this, I will continue reporting on another subject thread. But as of this morning, I can PLAY it, and I'm thrilled!
* Ergonomic issues not bad if you are about 6 1/2 feet tall and have extra-large hands. I am 5'8" tall, size-L hands, and I had to do lots of metal trimming and epoxy work, especially on the bottom R-hand keys. They look like a drug dealer's front teeth. But it plays and sounds wonderful!