FP4+ is one of my favorite 'standard' films. I often load it in my 'snapping' camera and leave it set to 125ASA. But develope I develope it in my 'normal' dev time for 100ASA - 11:30mins in ID11 1+1. This gives a good alround negative that straight prints G2 or G3.
When I rate FP4+ at 64ASA my 'normal' time is 14mins ID11 1+1.
I have never tried D76 as I have always had a good supply of ID11. I recently bought some emergency stock of D76 just in case the Ilford situation stopped supply, but as of yet I have not used it. Everyweher I have read says they are almost identical and the times can be interchanged.
Have fun :-)