Re: J Custom RG1502S
At the very least, a “spot run” means “there are not very many.” (6 and 12 seem to be the common claimed numbers.) I imagine you got a really nice guitar! Traditionally, J-Customs have been the top tier guitars in the Ibanez line-up. The problem with “spot run J-Customs made in 1998 for the Japanese market” is there may not be a wealth of documented information available and running into fellow owners can be difficult. With that said, Jemsite is probably the best place to learn about high-end Ibanez guitars built over the last 30 years.