I have a Takamine B10, the predecessor of the TB10. It was Clarky's before me but I think it's not the only one he had. I bought it from him in autumn 2011, IIRC.
It's unusual in that it has had lines and side-dots added, after factory but before I bought it. I hate the side-dots because they are, IMO, in the wrong place. I also wish it was still unlined. I have even considered having the fingerboard replaced but the expense puts me off. I have exchanged the complicated to use standard pre-amp with a simpler but also Takamine pre-amp.
I have gigged the B10 regularly for about four years with a folky-cum-Americana band with acoustic guitar, acoustic tenor guitar, electric piano and a percussionist, sometimes with full (but small) kit sometimes only cajon. I use old La Bella 760FS strings through a Mesa Walkabout 112 combo. The band and at least some audience members always comment positively on everything about how the B10 looks and sounds.
I play it horizontally and never upright. I added a strap pin on the neck heel for this purpose and it balances unproblematically.
The experience of playing it and its sound are both somewhere between a fretless bass guitar and an upright. Although any upright afficionado is probably not going to be impressed. The action will feel high to most bass guitarists but, IMO, that's partially responsible for the sound produced. The bridge is not adjustable and the intonation is in your left hand.
The body shape does not allow for proper arco playing; so if you are looking to bow it then I wouldn't waste your money.
The case is very large and, with the B10 inside, is very heavy. I use a (not cheap) soft but heavily padded cello case and the actual B10 case is in the loft with the end-pin.
Here it is with the rest of the collection .....