The service rep I've always worked with is Lionel Campbell. He always seems to be having his best day; he's just always friendly, understanding, and cooperative. I've brought my c5 z06 Corvette in for a couple mundane service appointments (Technical Service Bulletin warranty work) and a ripped axle boot (under my 7-yr warranty), and I've had two other unique experiences with the Service Department.
Clutch pedal inconsistencies made clutch engagement unpredictable; sometimes it just wouldn't engage at all. They kept the car for 4 days, testing it cold and I'm told, later, when completely warmed up (because the symptoms never showed cold). Lionel said they drove it for at least 20 times back and forth in their lot shifting gears through 1-2 and Reverse and in desperation, around the town and could never get the problem to re-occur. He claimed they probably had 2 hours of labor time committed to my car and couldn't justify any more time to an unpredictable intermittent problem. They returned the car to me without charge. It didn't cost me anything. (Futral did the work when the clutch finally died 8500 miles later, since I wanted to replace the diff with 4.10s [no labor nor parts guarantee under GM policy since 4.10s weren't available as an original sales option].)
I had one other experience with Service. I bought a used 2014 c7 z51 Corvette in 2016. It had 14,800 miles on the odometer. I took it immediately to Ryan to see if I could get all four of the chrome wheels replaced because they had very slight pitting. One of the four wheels had been curbed badly. (I worked in a Chevrolet dealership in California for 12 years in the late 80's; I knew my claim on two of the wheels might be considered frivolous- the pitting on those two wheels was extremely slight. The curbed wheel had the severest pitting, but it had been curbed hard, too. I didn't expect much. However, pitting is a true indication of an underlying problem during the chroming preparation phase; pitting would only get worse. As a [former] dealership employee, I could easily accept that Ryan Chev would not approve at least two of the four that I claimed; a car-show judge might not have spotted the blemishes I pointed out. I circled each blemished spot with a grease pencil and drove to Ryan.) Lionel directed me to Larry Hamil in the body shop; wheel warranties had to be submitted through the different department. They replaced all four wheels (in a "no questions asked" manner); they did say, however, that with that claim I could never claim wheel damage again. I was stunned at the warranty service. Almost 15,000 miles on the car; it was sold first 2 years and 10-1/2 months prior with less than 2 months left on the 100% bumper-to-bumper warranty and Ryan Chevrolet pushed my warranty claim through. Most aftermarket chrome wheels are guaranteed for only 2 years. I've never heard of a 3-year guarantee for chromed parts.
I've had only outstanding results with Ryan Chevrolet's Service dept.