I can't comment on the Roland because I don't really know where they stand right now in the market and if they are going to push forward with flagship arrangers.

But if you take KORG, the Pa800 is the budget version of the Pa2X and so that kind of reinforces what I'm saying here.

KORG add to this a little bit more than others do too to make the separation. For example, take the Pa1X Pro and the Pa1X. The pro edition is made from metal and has no speakers, and the standard version is made from plastic and does have speaker.

Even back as far as the i-Series. i30 no speakers, lower models did have speakers.

Yamaha PSR 9000 and the PSR 9000 Pro, again one with and one without speakers.

The Tyros Series 1, 2 and 3. Now speakers and not even standard.

Ketron Audya... again no speakers.

Regards
James