Using for home practice, with a pedalboard, I can run either my bass or my guitar through this and it sounds pristine!
The Bluetooth connects well, without a hitch, to my iPad, and the BT audio is exceptional quality (and doesn't sound like you're going through a bass amp!) Separate volumes for BT and Instrument, plus master vol, make this easy to balance.
Bass, Mid, Treb knobs are notched at 12 o'clock and have a premium feel. The respective Q/shelf for each one gives musical results.
Headphone output is good quality too. (I use Beyerdynamic DT 250 80ohms.)
The build quality is tactile and equally says this a professional quality device (rather than "Consumer Grade").
Jamming? Be mindful, this won't compete with drums, this is more appropriate for playing along with an acoustic guitar, for example.
There is no DI; the only output is the 1/8" headphone socket. I guess you could mic it if you wanted, but it wouldn't be loud as a monitor, so best not think of it as portable backline; it's for modest/quiet practice with fidelity.
Minor Niggles:
1) It came with a German plug. I'm in the UK. Fortunately, I had an adapter knocking around.
2) A limitation of this thing being so small is that the power socket has to be on the side, as there is a square rubber "speaker" that takes up the space on the rear. (The sound comes out of the front, I think the rubber "speaker" on the back is to aid the internal pressure so the front speaker works well.) Yes it would look tidier if the cable was at the rear, but tbh, now I have it, it doesn't bother me.
Overall there is a pride of ownership with a nice looking and sounding bit of kit like this; I do feel good when I look at it. I'm relieved not to be disappointed, as I have been anticipating buying one for some time.