OP, I purchased a NOS 579 in 2018 in the $15K usd range. MSRP was $22,500usd, IIRC.
I think it’s a great piece. It started off a little rocky because the chrono functions weren’t working properly (hands didn’t line up, and reset would land hands in arbitrary spots). It went straight to the Panerai RSC for warranty service. The RSC experience was OK but most importantly they fixed the problem. I’m not sure if the original issue was because it had been sitting for @4yrs at an OP boutique. In any event everything has worked great since.
I also found that they were hard to locate since only 300 LE pieces were made in 2014. I think I got lucky to find a NOS piece. With that said, I’m not sure what a preowned watch would/should sell for but it definitely shouldn’t sell for more than my NOS price. Unlike other LE pieces, this one hasn’t risen in price. IMO the Panerai market has gotten soft so many OP watches don’t command the prices they used to back in their hay day...this one included.
I was surprised to find out that they use Grade 2 Ti for the case...especially at this price point. Grade 5 is used only for the bezel ring because it can take on a better polish. I can’t seem to find the email from OP that stated this or I’d post it here. In use I haven’t found the difference in grade to be too significant, but I also don’t treat it like a beater. Grade 2 is generally softer but easier to refinish than grade 5.
The quick release (QR) strap system works as advertised. There are conflicting reports of the system binding up, so cross fingers that it won’t be a problem in the future. The reason I mention this is because the QR is press fit into the case, so if there’s ever an issue with the QR, the entire case will need to be replaced. Apparently there’s no way to just replace the QR. As limited as these issues are, I would have much preferred the traditional screw bar the OP use to use over a QR.
The last two points may seem like I’m being critical of the ref. but overall it hits a lot of the things I was looking for in a Panerai at the time. I coulda/shoulda bought a PAM 127 Fiddy when they originally came out years ago, but since I didn’t, I always wanted a 47mm 1950 case style. I love the sandwich tobacco dial, and gold hands. I also like the dial lay out (subdials are symmetrical) and they put the PR indicator on the back. IMHO, PR indicators on the front clutter up the dial and don’t look right...although arguably more functional. Combine all this with a desire for an 8-days movement and weakness for chronos....I had to have one.
Sorry for the long post but I hope it helps.