I don't really endorse any of these "budget" arrangers. I guess they're a good thing in the sense that parents will buy them for their kids at Christmas time- forging a future generation of arranger players?

But for the Synthzone / GA user base, I just can't imagine anyone here would find them satisfying. The Casio CT-X3000 is much, much better feature-wise than the EK-50, Roland E-X30, or any PSR-e-anything (less than the PSRs-670 anyway.) Maybe the best battery-powered arranger ever. It doesn't stack up to the MicroArranger feature-wise, but Micro's weren't ever cheap. And I wouldn't advise anyone to learn on tiny keys. What's a shame is Korg could have built the MicroArranger on their Kross Mk.1 platform. Battery power. Full-size keys, pitch and mod wheels above the keybed, and omit those tinny speakers. I mean- who doesn't have a JBL Charge or Ultimate Ears Boom these days?

Getting back to the Casio, the worst things about it are the keybed, and almost total lack of MIDI (which of course prevents controlling it from a high-quality master keyboard.) It sells for a street price of $269.

Even so, I would hold out for a used BK-5 or maybe Pa600. Unbelievable what they sell for sometimes, check out this auction:
https://www.ebay.com/itm/Roland-BK-5-Backing-Keyboard-Arranger-Keyboard-61-keys-/183811272817?hash=item2acc017071%3Ag%3AFGkAAOSwYihc2vRk&nma=true&si=OuFP8Qlia3Y%252BKLpeJ45Kj%252BfsMb8%253D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557

Once you drive a Cadillac, you'll never want to go back to a Ford!