I shuttled with ATC at buller yesterday.
Tracks were good a bit loose, but that's expected, could have used some rain the day before, we got a bit of drizzle through the day but don't know how much it helped the tracks. All said, the tracks are in good nick with a fair bit of work done to them recently.
Shuttle turn around was really good, never had to wait at the bottom, its not as quick as the chairlifts used to be but you could probably squeeze in 15+ runs if you rode solid and caught the first and last shuttles. We did 8 DH shuttles, with a big lunch break and rode some other tracks in the arvo. It is just a short ride 200m or so from the bottom of the chairlift up to the lower carpark where you are picked up.
Something to keep in mind when you're booking, its $65 to shuttle just the downhill tracks, but as we found out on the day you can book an "all mountain" shuttle pass for $80 which will also let you ride the shuttle from Mirimbah back up if you wanted to ride to the bottom.