Edirol was replaced with TTS. Both sound about the same. They are both synth patched piano sounds.
I guess it depends on the version of Cakewalk software that you currently have. If you have something that came with the Cakewalk Sound Center you have a fairly decent piano in that. It's sampled. Plus, if you are like me, not satisfied with the pianos and seeking more variety, Cakewalk sells a $20 add on pack with 10 pianos in it's Steinberg Piano's pack. I use the concert grands quite often. For what they are, what they sound like and what they cost, ($20)..... they are hard to beat as an all around piano for most tunes.
They don't sound as good as the specialty ones as several folks above mentioned.... such as Ivory, but then again, they also don't cost nearly as much. If the piano is part of a group, the need for a super clean hi-Q piano can be a bit less. If on the other hand, you are playing a piano solo behind a great singer, yeah, you might want to have Ivory sampling the part for you.