I own the EXR-7, so if you have any questions I can (hopefully) answer them.
It seems like the EXR-7 should fit you right, except one thing:
There's only one variation of each style (1 intro, 1 ending, 2 variations of the "main" part).
The registration banks are not really "one button press away" but they're pretty easy to call up.
Other than that I can't see why the EXR-7 shouldn't be perfect. The sounds are good, the keys are good and the sequencer is also good (and very easy to use).

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Robert.