Bought my Yukon XL Denali from Steve M. in Newark (Great experience as well). It has been service at both Pataskala (horrible experience last time) and Newark (Great experience both times). I will focus this review on Newark.
Brought the vehicle in for one of the included oil changes and to have a couple minor warranty issues looked into. They were able to fix both issues and the oil change in 1/2 a day and they found another issue as well that was covered. I felt that John actually listened to my concerns instead of blowing me off like Pataskala did, which was refreshing, and I think it helped to actually get to the root cause of the issue. I would definitely be back to Newark, even though it is quite a bit more out of the way, but it seems to be worth the drive.
A side note, Pataskala used to service my Buick many times without issue, so it may have been a one time problem there as well.