Pyro Ball
Pros:
+ No recoil
Cons:
- 90% Accuracy
- 8 PP
Flare Blitz
Pros:
+ 100% Accuracy
+ 24 PP
Cons:
- 33% Recoil
Since the amount of PP of the move rarely ever matters, the matter of which move is better pretty much comes down to whether or not the perfect accuracy justifies the large amount of recoil that comes with it. They share the same power, so there is nothing else differentiating the two moves. Pyro Ball seems like the clear victor here because the only relevant downside, the lesser accuracy, is still a very reliable 90%. The recoil from Flare Blitz, on the other hand, is a very noticeable drawback.