HI Christian

I've owned the Tyros 2, Pa2xpro, Audya 4 and Audya 5. I have just purchased the Tyros 4.

I would stay away from Ketron products. They are unreliable, poorly supported by the manufacturer and US Distributors, and are not very intuitive. It is very difficult to obtain 3rd party styles and almost as impossible to create your own. Some of the style categories such as Jazz and Big Band are very limited. I think the board only has 300 styles. I also was not impressed with the guitars and synth sounds. Of coursed the Ketron drums are awesome as are the organs and Saxes. The Ketron reminds me of a Wersi keyboard. You really need to be technically savvy and adventuresome to own one of these keyboards. If you are an entertainer and need reliability, I would look elsewhere.

The Yamaha boards are so very polished, highly supported, very reliable (hardware wise), and have the Best Voices and Articulation implementation on the market. As for support, there are thousands of styles and style conversions for the Yamaha's and at least 4 top notch web sites/forums devoted solely to Yamaha keyboards.