Jems aren't made in Korea, they're made in Japan, in Fujigen. Only the lower end Jem555 and Jem Jr. were ever made anywhere else.
If yours is made in Korea, its a fake. The serial number should start with F then 2 digits denoting year of manufacture, then the digits will notate the production number for that year. If its a real Ibanez neck bolted onto a Jem body, with a decal supplied perhaps (Lots of people make Ibby project guitars, and ibanez decals are widely available), then the Korean necks subscribe to the same numbering scheme but the letter will be C, for 'Cort', the factory that ghostbuilds all korean Ibanez models. (Until recently, as due to Cort shutting shop, production has been moved to Indonesia. I don't know the prefix letter for the indonesian factory.)
Also, the LA custom shop was for years open to the public, however Ibanez closed it for the public due to waning demand. The outline of the shop itself consisted of numerous custom graphic finishes, and also a selection of RG pickup configurations for those people who wanted non-standard layouts such as H-S, without buying an RG565 sicne they may have wanted alternative finishes.
It runs today as a shop dedicated to "endorser" models, which is different to signature models. An endorsee artist is recognized as PLAYING the guitars of Ibanez, but not having a signature model. The artist can request custom modifications to an existing stock guitar and they will then be performed at the LA custom shop. An example is Dave Navarro's PRS tremolo equipped RG, or the original version of the 27 fret Xiphos. However these guitars will never be marketed as signature models as say, the Jem or the JS are. They are SINGULAR, NON-production guitars constructed as prototypes for very specific players. in nearly all instances of actual signature models however, no modifications are made or needed, therefore the artists guitars themselves come directly from the Fujigen plant.
In actual fact, Its well documented that apart from crazy modifications done to some guitars like FLO and PIA, all of Steve Vai's onstage Jems are built in the Fujigen plant. Even EVO was a stock Jem7VWH, and to all inents and purposes, still is. Vai has stated numerous times in interviews this fact. Not to mention, a major design reason according to Vai himself, for the bolt on necks, is so that if one broke, Ibanez could just send him a production neck and it will return the guitar to its original specs with no costly custom machining.
Also, with the closure of the Cort factory, and the introduction of the S5470 and SV5470, anything Ibanez make with 'Prestige' branding, is Japanese made now, unless its old stock S prestige models of numbers 2170 and below (Or old stock of the 7 string S model, which was also korean).
Regardless, the Korean Ibanez guitars are by and large of great quality, hell, I own an S2170. My only gripe was the stock pickups, but Ibanez have now revamped their prestige lines for 2009 and are supplying Dimarzio combos in many of them. Also, the original ZR tremolo system had an arm holder flaw, which has since been addressed with the introduction of the ZR2.
I'd say you need to check on what you actually have there, and do some research. Jems are fine guitars and I've played more than a few that have all been of consistently high quality. My favourite being a sparkle blue 2002 model. In fact, the last major QC issue brought up in relation to them was to my knowledge corrected some time ago by tightening up the tolerances on the routing for the vine inlay so that less/no gaps needed to be filled around the inlay itself.
Yeah. I know more about Ibanez and guitars in general than anyone reasonably should. Suffice to say, I think if you've managed to find a jem that plays like an RG350, you've not found a jem. For one thing the neck profiles are completely different and so is the fretwire. Not to mention a 350 would have a nut volute, whereas an 02 Jem wouldn't. Does yours have an ebony or Rosewood board, and can you confirm the serial number for me? If its an early 02 production number, its much more likely o have an Ebony board than rosewood. Later in 2002 however production switched to rosewood in preparation for the 2003 model changes which included a switch to the Edge Pro bridge without locking posts, and I believe the aforementioned tightening of routing tolerances was done around the same time.
UPDATE: After some discussion and Sodacake giving me the serial, number, it was established that unfortuantely his guitar is NOT a Jem7VWH in this post