I soloed in the R22 at 13 hours, which was the school's insurance company mandated minimum - no prior flight time, but several hundred hours of military helicopter enlisted crewmember time. That definitely made a difference, I wasn't freaked out just being in the thing & was comfortable on the radio.
It didn't matter though in the long run, when getting my CPL later on I had to burn off 10 extra hours of dual training to meet the FAA minimum hour requirement there.