I'm not sure what the neck is made out of, but it is fluid and easy to play all around it. It is easy to play both for traditional bass playing or for slap bass. It is easy to play all around the neck, including the top notes. The bass is somewhat heavy, but isn't inconvenient to pick up and bring somewhere. The inherent sound from this bass is extremely unique and it is easy to get a good sound from it.
The Rickenbacker 4000 definitley suits my style of music as I play a lot of classic rock type stuff. It is a great sound for playing kind of a "lead" bass. It is great for slapping with and the sound has been made famous by players like Chris Squire from the band Yes and Geddy Lee from Rush. While, it certainly fits in with the whole progressive-rock sound, it is more versatile than just that and sounds great for rock and jazz as well. It is awesome to throw a little bit of overdrive on this, but even without it it has a ton of crunch to it.
I've been using the Rickenbacker 4000 for about three or four years. It is one of my favorite basses because of its unique tone, which is one that is hard to emulate with any other bass. This bass has become famous and well used because of this tone and also because of the awesome look and feel to this bass guitar. Just like its sound, it looks unlike any other bass and its ease of use and playability is top notch. The Rickenbacker 4000 is a great bass guitar for bass players on all levels and is definitley worth the reasonable price.