From what I have read from reseach utilizing the Kraft Music website here in the USA:
Yamaha PSR-SX700 - $1,499 USD
Yamaha PSR-SX900 - $2,199 USD
Korg PA4X-61 - $3,899.99 USD
Yamaha has really marketed these SR-SX units to be their middle of the road arrangers.
They are roughly $200 USD more expensive than the Korg offerings in similar price.
Korg PA700 - $1,299 USD
Korg PA1000 - $1,999 USD
The Yamaha offerings have some pretty impressive specs (such as the EFX routing and insert effects (5 on the 700, 8 on the 900)). That can mean a lot for varying one's sounds.
I still think that Korg has them beat.
Maybe this will prompt Korg to add some features in future OS updates to make their products even better than they already are...
I would love to see 5 insert effects in my PA700. I have many other synths in my collection, including the M50 and Kross. I LOVE how Korg set up the EFX in the M50: 5 insert effects, 2 master effects, 1 total affect.
I know that the M50 is a synth and the PA700 is an arranger. In total the PA700 has 3 insert effects when using the sequencer mode. That is not too bad. But to have 5...it would allow for more detailed creation of lead guitar sounds...
One feature that Korg is behind on is the creation of WAV files; all of their PA series currently on offer only allows for MP3. With that said, you can create a 320k MP3...but WAV would be a great addition for lossless audio recording...
The PSR-SX700 does have a dual speaker system and the Korg PA700 has a single speaker system for each side (L/R). The Yamaha 700 might have a bit more clarity as a result.
When the Yamaha units do become available, I may take a look at them...I will NOT give up my PA700 for anything
Grace,
Harry