Roland didn't have a lot of choices when it came down to pianos to sample...they can't/won't sample Yamaha(except for the CP70/80) and that only really leaves Kawai or Steinway (and maybe Bosendorfer) as Roland do not make their own acoustics.

I doubt if they sampled a Young Chang,a Pearl River or a Samick...

I really liked Roland's SAS pianos...pity they didn't keep it up and delop it further but I guess it may have reached it's potential and was more hassle than sampling...SAS did a great electric piano sound....they also used it on the Roland (Rhodes) VK1000 and it did a great Hammond sim.

Ian