I use low priority exclusivley unless I have more than 1 interrupt, and one 'or more' needs priority over the lower priority interrupt task.
Ok,
But since all the 18F's default to High Priority on power-up.
You have to first Enable Low Priorities by setting IPEN ...

RCON.7 = 1 ; enable interrupt priorities

And clear the corresponding priority bit for the interrupt you're using ...

IPR1.5 = 0 ; set RCIF to low priority

And always remember to use GIEL INTCON.6 instead of GIEH INTCON.7

Then, does that give you anything that the default High priority doesn't?
Other than more statements to write.

Well, DT_INTS doesn't really crash, it just won't compile with only LP ints because it's looking for something that isn't there. And I never saw a reason to try to change it.

Perhaps it's just a way of thinking and I could make DT_INTS allow LP_INTS only.
But if there's a valid reason, I will definitely do it.

Q: Is there a reason anyone can think of for using only Low Priority Interrupts?