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Thanks for your interest.
Please note that I generally can't speak about future plans/versions.
If there should ever be one, though - and this should neither be seen as confirmation or denial of any plan - it will most likely lack a few features and drivers compared to what can be made available outside of the Mac App Store.
My general advise to questions of the "Should I buy software XY now - or wait?" is this: if you've good use for the software now, buy it now. There'll always be a next version/edition/special offer that one could wait for.
Best regards,
Felix Schwarz