So I have owned from new a gorgeous Miami Blue JM. I ended up selling it a couple of years later and here are my thoughts and findings.
Miami blue + maple combination on a JM is the most beautiful guitar I've seen, bar none. The satin neck and the shaved heel were amazing. The finish was impeccable. FWIW the lacquer on the fretboard was applied on top of the frets and after some playing it started chipping off from the frets (maybe this is the standard procedure?). I liked the replacement of the useless (to me) rhythm circuit with the pickup in series selection. The shielding and grounding was done very well.
The guitar came with a significant defect, one of the pickup height screws had been screwed in at an angle (not at 90 degrees) and so it could not lower or raise the pickup... I had to fill the hole and redrill one at 90 deg.
Another significant defect was the neck pocket on the body. It had been badly routed and it only made contact with the neck at a narrow ridge around the pocket, hard to explain in text only. I haven't seen such bad quality in any guitar in my life. Unacceptable flaws for such an expensive guitar.
The Panorama tremolo does feel a bit different than the traditional one. Loved the trem arm adjustable rotation tension, so it can stay put instead of hanging/droping down. Also no play in the trem arm socket, big plus. That said, the stock Panorama trem system has very limited range if you use heavy strings (11+), as I assume most of the forumers here would already know. I prefer the feel (force vs pitch and location of pivot point) of the traditional JM tremolo, don't see the need for dives on a JM; that said, the trem arm behavior is amazing on the Panorama.
The bridge came with thimbles at the posts to keep it from rocking. I removed them and had it rocking. The mustang saddles are ok I guess. I like to set each saddle height indiviually so I would have preferred saddles with height adjustment. I struggled quite a bit with getting a good balance of string action accross all strings and was never 100% happy with the result).
Personally, I could not get used to the shape of the neck, it was too thick and had too much shoulder for my taste, especially at the higher frets (I have small hands FWIW). I couldn't get used to the tall frets either. I couldn't get a medium-low action without bends choking so I suspect something was off at the higher frets, can't say for sure. I was also unlucky and that particular guitar was quite dead sounding acoustically.
The original pickups were nice I guess, I tried changing them in case I could improve the dull sounding guitar. It didn't do much to remedy that. I tried the PV65 pickups but wasn't crazy, I had in my mind the AVRI62 tone and they were very far from it. The low output didn't do it for me either (they're lower output than all of the SD offerings and the AVRI62s I believe). As a result they don't push my reverb tank like the AVRI 62 did, which I do not like. Other than that, they sound good. Crystal clear, balanced, scooped sound. Very "polite", not too trebley or ice-pick-y (even with 1Meg pots). They have bass but even at the neck pickup it is not overbearing. The AVRI62s imho have a pronounced mid peak (like a wah but no so pronounced), a middy honky character.
Had to eventually sell the guitar with a heavy heart. I may try my luck again with a Miami Blue JM just for the color, I would replace the neck to something I like more. For now I'm ok with an AVRI62.
