Two one-day rentals recently at LAX. First time round, had an older car which had 30k+ miles on it, which prompted a 30% "high mileage car" discount. Second time round, got the 2017 A4 which was really quite nice.
Overall thoroughly enjoyed the experience. Staff service was great, and the whole thing worked quite flawlessly.
I think the pricing premium is warranted for the overall experience which they offer.