Does anyone have any thoughts regards these 2 keyboards, ie which is the better? Thanks

Both have strong points. If you want to use vocals through the keyboard, the 740 is better. It has harmonizer and fairly extensive microphone processing. The 5000 mic preamp is bad.
Also consider compatibiity with your primary keyboard. It's nice if they both use the same format as far as songs, styles, sounds, etc.
Also, the 740 is much lighter in weight.
The KN5000 has some really neat features, such as creating styles from songs, style conversion software and color display.
It all depends on your specific needs.
Don

Thanks Don. I've heard the harmonizer in the psr740 is not all that good tho I haven't heard it myself, any thoughts, also which has the better editing ? Thanks.....

Actually I thought the harmonizer in the 740 was pretty good. The mic processing in it is somewhat limited though.
The harmonizer IS much better in the 9000. With OS 2 it has more parts and it has more options. You can easily assign and save parameters and settings to registration memories. It works well in Vocoder mode, Chord mode and Song mode.
Speaking again of the 740, it wasn't too long ago that I paid more money for a less capable harmonizer than the entire cost of the 740!
With the 9000, you get separate 3-band e.q. for the mic, a compressor, dedicated DSPs, and extensive editing capabilities.
Hope this helps.
Don