To me the Tyros 5 piano still sounds like the older CF3 sample of the main Motif XS piano - it is a bit too bright and sounds like a pop piano. Obviously the more wooden S6 piano sample of the Motif XF (and MoXF) are not implemented in the Tyros.
I especially cannot understand why piano packages such as the free CP1 piano for the Motif + MoXF flash are obviously not offered as a Tyros expansion. And it seems very complicated to get third-party pianos into the Tyros flash (only via PC and voice editor - is it finally available for the T5 at all?)
It seems Yamaha thinks that the average arranger player is satisfied with a rather bright piano that doesn't have a lot of depth.