I was joking, I didn't just buy it cos of the size (I actually lost the auction, so I didn't buy it at all!).
I do however do my music with another person who lives 1.5 hours from me and travel there by train. Obviouslly a compact keyboard that can be chucked in a bag and carted off on the train is very useful.
I figured this size advantage would encourage me to get more use out of it.