After years of thinking about a synthesizer, I finally bought a used one to see if I could make use of it playing jazz. Here is what I've learned in the first few weeks.
You need a cable. The synth requires a 13-pin cable to connect to the pickup. Roland charges a bundle for these, though you can get after-market versions that are cheap in both price and quality. The guy I bought this from did not include a cable, so I ordered a Roland one online.
You need a pickup. This one did include the GK-3 pickup. The pickup is not a conventional guitar pickup; it has six individual cores and sends six signals back to the synth. This allows all kinds of gymnastics with the strings that I'll mention later. The pickup and accompanying control module will fit lots of guitars, but not all. Notoriously, they will not fit a stock Telecaster because the plate has a high lip on it. People have notched their plates to allow the pickup to stick out, or replace the plate with a flat one. I mounted mine on the PRS, the best fit of any of my guitars.
The manuual was a good effort but is not intuitive to use. Like my Boss JamStation manual, individual sections make sense but it doesn't hang together very well. I think of it as a reference book, not a tutorial.
It does so much that it's overhwhelming at first.
It is big fun, but I'm not sure how much I'll use it on jazz gigs. It seems oriented more towards guitar, amp, and effects modeling for the guitarist in a cover band as opposed to the creative artist. It certainly does have a richness of features that do allow that creativity, but I don't think that's how it's typically used. I did play two tunes on it at a recent gig. First, Autumn Leaves using the vibraphone preset.