The Say It Again board is used on Centaur II, and is a pretty simple board really... except for one problem - the SAD4096 chip. This chip is used in many older effects pedals (guitar effects), and is a very sort after chip for many of the "chorus" type pedals. It's renowned to have a nice sound... and renowned to be a high failure part (even if just left sitting on the shelf unused!)
Anyway, this chip has not been in production for many years, and is the main reason for the Say It Again board to not work. There are supplies of them available, but you need to buy in quantity... something most collectors will have no need to do if they only really need one or two of these chips.
I would go for the new board as it is using new parts, so hopefully the SAD4096 chip will last a long time for you.