This is, of course, one of the more controversial and discussed bass topics in the bass community. I'm a luthier and repairman, for a very long time now. I've worked on everything you can think of. There are typical issues with new instruments, and with incredibly expensive, rare vintage instruments. I have seen plenty of 20k Fenders with 'S' curves in the necks, that people love, and are happy to own and play, even with medium high action. I've seen some awful stuff from Fender, Gibson, Hofner, and the basses we love to either covet or slam, Rickenbackers.
In my time doing repair work, I've replaced truss rod assemblies, and think back, that I probably should have replaced a lot more of them. I've always had my issues with the concept of two rods, and to this day, see Ricks with really bad 'truss rod nose dive' as I call it, where the threaded ends warp so much, they dig into the rod cavity wood, and you need a specially machined 1/4" open end wrench to adjust them at all. I have rarely seen this on any other instrument, but have seen it many times on Rickenbackers. ONE GOOD, double acting rod, inside a STRONG, nice piece of maple, or other suitable luthier grade billet of wood, would be far better. In my opinion, too much wood is removed from the neck to facilitate the installation of the two rods and the aluminum blocks. The bridge design on the 4000-4001-4003 series, is just wrong. No individual height adjustment, soft bridge material, and the intonation adjustment screw access is terrible. They'll lift over time, as well.
I disagree about the finish comments- I think Rickenbacker does some nice woodworking, and the instruments they build are generally fit and finished well. Rickenbackers have a distinct, well known sound that no other basses have. My experience is, some 4000 series basses are duds- that sound like you're hitting a heavy rug on an outdoor clothesline with a shovel..and others ring and have killer tone.
I have always wanted a lefty 4005 Rickenbacker. I think John Hall has said they'll never make another 4005. There were some lefty ones built, but the last one I saw was a six, at $16,000.00! They're very rare. I've seen some luthier built ones, but still not feasable for me to suspend all my repair work to build one. So, YEAH, I ordered and modded a lefty 4005 from China. It was 400 bucks. And NO, I do not recommend the average player buy these basses from China. I expected problems, and I got 'em. And, I've taken care of most of them, and gigged it Saturday night, and had a blast playing it! I upgraded the tuners, and pickups. It has some issues, for sure.
A real Rickenbacker would probably be $5k, if they ever decide to make one. Would I take a rare new 5k- or vintage 25k bass to a gig? No. I swear, it sounds a lot like a genuine 4005. The issue here, is that Rickenbacker does as it sees fit to do, which as an American business, they have every right to. Would I buy an Indonesian, or better- a Japanese custom shop built 4005, for say- $1,000- 2000.00? YES.