Just a thought, but you might find it a chore to clear a G34 length slide from the holster, especially in compromising (sitting in a car) situations.
Somebody above hit the nail on the head, longer is better right up until it’s not.
And, just my anecdotal experience, but the thinness of a firearm makes more of a difference in the comfort department than slide length. The P365XL, G48, Hellcat Pro’s are the kings of AIWB.