A320 series FMC & instruments supplier differences
 

I have question to you Airbus guys from a hitherto Boeing/Douglas pilot suddenly faced with fleet planning speculations.

The A320 apparently comes with a Honeywell FMC (Pegasus) std but alternatively a Thales/Smiths unit. Any significant difference in operation/interface?

Also option is a Honeywell instruments package vs. Rockwell Collins/Thales.

I would appreciate knowledgeable input from those with experience as to pros and cons of each setup.