I expect a pair of monitors with accurate sound to cost more than any of these arrangers. Additionally, a room where it’s used should be acoustically accurate as well, which can cost even more. I doubt that built in speakers are accurate in any way, also, I think, an arranger itself is adjusted to sound well with its speakers.

As some professionals say, even if speaker is labeled as “monitor” it does not guarantee much, especially when it’s not very expensive.