It seems almost universal reading through this thread and others that for those with significant chronic medical issues, 8.5lbs has proven to be a fairly firm limit on weight. This is what makes my Sterling at 8.4 "just ok" and keeps me searching for even lighter weight instruments.
Just to reiterate what has been said in previous pages, medical conditions can change all of this preference stuff in one stroke.
Pain of the "I pushed a little hard at the gym last night" variety is one thing. But any kind of medically-related chronic pain or discomfort that has even a hint of neurological origins (numbness, tingling, etc.) should NOT be ignored.
For that reason, I now have a hard-and-fast 8 1/2 lb rule for basses that I'm going to play standing up. I just can't afford to let my chronic back problems escalate any further than they have over the last 40 years.
I am still enjoying a busy gigging schedule, I love playing almost as much as life itself, and I'm not ready to be forced out by another injury. That's it, that's all...
