I nearly bought a Thumb last year, I heard of an NT going for £800 when looking for a new bass but didn't follow it up. My Dolphin isn't too heavy I doubt the tone cavity takes much off the weight but the reinforcing rods in the neck probably make up for it. As for sound, yea I can make it sound zingy, it also does good impressions of a Precision a Jazz and even a Ric. I get a really nice low growel out of it, even the guitarist I jam with has commented on how nice it sounds, doesn't sound tinny like other basses (his words not mine).