I concur that the overall sound of most all of today's arrangers is very good (including the PA50), but I also believe, if you can afford it, there's a substantial sound improvement, plus gaining many worthwhile new/improved features when you opt for the TOTL model. Bottom line: get the keyboard model that best meets your needs and budget.

I also want to point out that nobody on this forum residing in the US should be paying even close to $5000 dollars for either a Tyros 4 or the 61 note Korg Pa3X. Fact is, the actual 'street price' for them is more around $3400, with the difference between them relatively close. I purchased my Tyros 4 from Synthzone member dealer Frank Ventresca (AudioWorks) and recommend him highly.