I got the original Tonewood amp as a gift about 5 years ago, I've used it with my acoustic here and there. It comes with this X-bracket that you stick inside the guitar, and this has magnets on it that grab the actual amp on the outside. Once you plug the guitar into the Tonewood, you could even take the output from the Tonewood and put it to a PA or a separate amp.
There are some cool effects - not just chorus, reverb, delay which are really nice. Also distortion (not great), autowah, tremolo, and volume swells IIRC.
It really adds some nice dimension to acoustic in the room. Turn the Tonewood up a bit and you get some warmth, shimmer, and space that I kind of miss when it's off. You have to position it properly on the guitar so the little speaker is flush against the back, otherwise it can cause feedback. Turn it up too much and depending on your input gain and FX settings you might get a bit of feedback too as it causes the body to resonate.
IMO it's not too hard to manage, just start with the gain/volume low and you'll find the sweet spot!
