RD-700NX or FA-08?

[MairMarco]

I already own a RD-700NX Stage Piano. My question is of I shoud keep my RD or sell it to buy the new FA-08.
I need it for live usage!!!

What are the advantages and disadvantages concering sound and versatility or possibility?
Especially vintage Instruments like E.Piano and Organs are very important just like the acoustic pianos.
What do you think about the Super Natural sounds in the FA-08.
The keyboard of my RD is great but less important.
Effects are also very important...
Any other indications about the two boards (expecially the FA) may be important for me...

I hope I can get here a lot of information that are important. I use my keyboard for live usage
Thx