From knowing what the PCreek file sounds like on my G70, I'd suggest adding 5 or so (or to taste) to the Cutoff parameter on the E50 sound... You won't hear much difference when 'spanked', but it sure helps brighten up the low velocities just a bit more...

I have no idea why Roland decided to darken the pianos in the E80/60/50 compared to the same piano in the G70. To my ears, the G70 sounds pretty much identical to the FantomX 'Ultimate Grand' patch, still considered one of the best ROM pianos around.

They all sound roughly the same when hit hard (or Key Touch is set to LOW), but I think I really DO hear them get darker at lower velocities... in fact, just a tad TOO dark for me.

What IS that other piano? An older Korg stage piano? An old RD? It's too fat for a Yamaha, isn't it (and quirky)...?