The 20-year-old Briton, who is racing in the Formula 3 Euro Series with Mucke Motorsport this season, was grateful for the opportunity to sample a sportscar for the first time.
"I have to say a big thank you to AUTOSPORT and Aston Martin for making it possible because this isn't the sort of thing a driver in my situation would usually get to do," said Sims.
"It was a really good car to drive. Having spoken to David Brabham and Darren Turner beforehand, I was expecting something similar to the DTM car, which I got to drive in the award, just a bit heavier.
"And it was just that. They use tyre warmers which gives you a lot of confidence to get close to the limit straight away - a big help when you have a limited number of laps."
Sims is currently lying eighth in the Euro Series standings in his rookie season and is eager to keep moving forward as he gains experience.
"I made a few too many mistakes in first few races, which I've learned from," he said. "I had a very good Masters, and the races at Norisring at Oschersleben were good too. We're only halfway through the season so hopefully it will keep getting better."