I know it isn't what you want to hear but what you are doing is probably preferable.
Two reasons.
1. PD9 isn't particularly good at estimating disc size so burning to folder is quite a good intermediate step.
2. PD9 can be a bit flakey in burning discs and Imgburn can also verify the data.
Panasonic SD9, Panasonic TM700, Panasonic SD600, GoPro HD Hero.