Yes very nice, maybe..
But also very old...It's simular to the SP0256 IC.
I tried the Sp0256 and it works nice, but it also produces a robotic un naturale voice.
Have you thought of using the RC8650 instead?
It's a little more expensive in low quantity, but I
believe it to be of better quality than the Winbond
unit.
I have used ISD14XX chip very very nice chip i have complete information about that chips application notes data sheet interfacing with micro and lot more if some one intrusted i will upload all information here