Re: Old vs. New Ibanez JEMs.
I just bought a 2004 JEM7VWH. I played a few before buying it and I do not believe that Ibanez are fraught with quality control concerns the way some other companies (that shall go unnamed).
I found that the QC is top notch - frets came levelled, no uneven edges or rough patches. I don't think that Ibanez's Japanese made guitars suffer from QC problems.
Like some have mentioned, they do cost a fair bit, but tend to maintain their value a fair bit better than your typical shredder axe. I disagree with the general consensus that Jems are RGs with a handle. I believe that a lot more QC and attention go into producing Jems, and the components that make up the guitar are a lot better too.
BTW, all jems (with the exception of the 555 models) are made in Japan. Any production QC concerns are usually associated with the Korean made prestige and s series, which are rather s**t in my opinion.
The playability is second to none. Notes just fly off the guitar, and the evolution pickups are very hot with a heap of harmonics, but I understand that they do not suit everybody's style.
The only downside to the guitar is its perpetual association with Steve Vai, which can be a double edged sword. All in all, its a 'love it or hate it' guitar. As for me, i'm quite happy to play and own a jem simply because it feels and sounds like I want it to.
New or second hand?
Something I've found with ALL guitars is the tendancy for necks to warp over time. This can occur with all brands and makes of guitars, not just Ibanezs. This generally occurs over time with large changes in humidity and climate.
So if you can find a good second hand Jem that is worn in with no neck warping, buy it after testing it out thoroughly. Chances are, the neck wood has aged sufficiently and will resist further warping in the future. If you buy a brand new jem, you will have the benefits associated with a brand new guitar, but you risk the neck warping.
I find that the S series (wizard) necks are more prone to warping and changing shape over time due to the thinner profile. The jems are a little bit thicker than the wizard necks so hopefully this won't be a problem for me in the future.
Check out jemsite.com for more info on Jems. These guitars have a dedicated following, and the forumites there will be more thna happy to address any questions you may have regarding specific details of the guitar.