Nope... having owned both for an extensive time.... i dont think any of them is a wrong choice...

Different boards with different charms... as said many yamaha home players will only be confused when moving to Korg...

And while both boards can be used with great succes by both homeplayers as well as professional players on stage.... its obvious to me, that the pa4x is designed much more with performing musicians in mind, while the tyros5 is designed much more with home players in mind...

That is also part of the reason why Korg is so popular on these boards.... most of you are professional players, with professional and gigging needs...

So does that make the tyros 5 any less? No, many features on the Tyros 5 are still unsurpassed. but for a gigging yamaha player, the psr-s970 might even be a better choice then the tyros5.. as most as the extra features of the tyros 5 will barely be used on stage.. and the new features of the psr like live knobs and arpeggiators look to be an asset for playing modern music if needed. .. i think if you can live with the psr keybed, its a wiser choice for stage then a tyros5

This however can not be said from the korg pa4x vs the pa900...