Diki you are correct that the FP-E50 only has two variations per style. The FP-50/FP-80 also had only two variations per style, as did all Roland arrangers before the G-70. This fact by itself doesn't mean that FP-E50 styles won't play in older Roland arrangers, perhaps subject to revoicing.

My point was that style compatibililty (and incompatibility with the E-X50) supports my theory that the FP-E50 is built on the legacy OS of the FP-50 (which itself was intimately related to the BK-series.) Thus the FP-E50 is a descendant of the true Roland arranger line, whereas the E-X50 and E-X30 are impostors with Yamaha-influenced OS, style format, and chord recognition.

If you accept my claim that there is an "heir," the first in almost eight years, I see this as hope that the bloodline will continue!