I think GNR is a fantastic game personally. Once again it is one of the those games that was made for a home environment where you can fully see and experience the game and what it has to offer IMHO. I doubled the most money I have ever spent on a pin in over 30 different machines in order to get a JJP POTC, then I went even higher than that to get my GNRLE. Eric just seems to know what I think a home use machine should be. If I am paying a premium price then I want depth, I want challenge, I want variety and I want an experience. GNR checks all the boxes for me. For weeks I was figuring out new things and I still am to this day a couple of months later. GNR, much like POTC is not a game you walk up to and figure out in a few plays. People say, "It's a multiball fest" but they don't understand how or why to start them. They serve a big purpose in the game and they can only be started once per song, so it's not as often as you think. If you are just getting them randomly, then you are doing it wrong. The patches. Much like characters in JJPPOTC, you could take a course on the patches, their benefits and the group patch benefits. I'm still figuring strategy out with those. The album modes are all unique, single ball, and very challenging. The scoring for them needs to be adjusted, but you can't argue with the variety. Then add in a couple dozen+ songs with unique rulesets and the ability to build up value in multiple different ways before starting them and during them, not to mention the risk / reward of the jackpots during the songs. Do I push it and go for crazy high jackpots or cash out and live to play another song (hopefully)? Finally, the sound and light show are second to none, period. It is the most played game in my collection currently by far and it absolutely blows guests away like no other game when they come over and see it for the first time.
Personally, I think people are selling because there are a lot of them out there now and the money it takes to buy one is a ton of money to have tied up in a game when there are more and more increasingly expensive games coming down the line. In addition to that, honestly many of the people I know that are selling a GNR are not the type of players a game like this is geared towards. Casual players just want to flip during a song and that can be done way cheaper and easier on a LZ or Rush for instance...you don't need a GNR for that. Plus, many people nowadays have to sell a pin to get one for space and financial reasons, so a different, challenging and very expensive game like this with a now large amount of availability for a JJP game could easily be low hanging fruit for many.