Eitehr one's only two cycles long ...

Oh Richard, have I infected you :)

using
MOVC A,@A+PC
or
MOVC A,@A+DPTR

Eitehr one's only two cycles long ...
but you have to load the accumulator and, in one of the two cases the dptr as well. Of course, in the case of loading long strings (and no other dptr action) that can be insignificant.

also, most non-assembler tools will use @dptr where you have to load the dptr as well.

Erik