bear with me if this has already been answered - I looked around for quite some time on the Internet and this board, and couldn´t find a definitive answer to my specific question.
I play only at home, and kinda fell in Love with the Grand after having read a lot about it - played it the other day for an hour at my local shop, and now I really want one

The big question for people like me (playing only piano, only at home but still interested in a bit of "tinkering" with the sound) is of course - Nord Piano 5 or Nord Grand?
Untill yesterday I was convinced that they are identical in terms of the electronics, the only difference being the (imO) superior action/keybed and the size/design - but right now I am a bit confused..
tl;dr:
Is it possible to layer two Piano Samples together on the Nord Grand ? - I´d love to be able to do what Chuck Piano Man is doing here: (Hope the youtube link is ok, it is his "create your own unique piano sound" tutorial - he basically plays two piano sounds at once.)
If not possible, can the same effect be attained by loading a Piano sample into the synth section? If yes, what are the shortcomings? (except the synth memory being full quickly..)
Thanks for your help,
cheers from austria