The SBOX isn't one I know anything about - mine is an internal modchip from Modchip.com. I thought that SBOX was only for US/PAL PS2s. You say you use it - so you do boot with it and DVD Region X? EA Games will need patching with a USB based Modchip. Our friend DAL is a Forum expert on DVD Region X booting (I use the Jap Utility Disk) and possibly he'll come into this thread.

But back to your JAP SCPH 30000. This should really have a modchip.com internal modchip. The latest versions work with DVD RX, but I haven't implemented it preferring to stay with their beta chip and the Utility Boot Disk. I'm moving tomorrow to the ORIGACHIP (Madeira Games, +44 1485 570256) which allows import originals to be booted. The only snag for you is that the Jap 30000 appears not to be supported. But call Madeira Games and put the question directly to them.