If I understand correctly, you have a design with a PC Board currently in layout. Changing horses at this point would involve a severe schedule impact as you are no doubt aware. Unless you have uncovered a showstopper in the CUBLOC controller, I would advise you to go for the best result possible rather than the best possible result.
I can also recommend the AVR line form Atmel. They have good support and there are a range of development tools both free and commercial. The in system and self programming capabilities are excellent. Here is a link to the 8-bit line:
Atmel Products -Microcontrollers - AVR® 8-Bit RISC
Good hunting