Eric Tinkler's men won 1-0 last night as Sim netted his first goal for the club seven minutes into the match at Cape Town Stadium.
"It was one of those games," Sim said. "We played such a good side in Kaizer Chiefs and the crowd, what a great atmosphere. I heard some big things about the crowds here. Hats off to our boys who were very resilient and defended well enough to get the win."
The Australian is impressed with the standard of the PSL and the family atmosphere at City, who were only formed around two months ago when ex-Ajax Cape Town boss John Comitis bought the topflight status of Mpumalanga Black Aces.
"What I have seen of the league, it is a very strong league. There are some very, very talented players. You see some of the boys Kaizer Chiefs had and they were excellent. Our boys are very good as well. So I have been very impressed with the standard here."
The former Sydney Wanderers midfielder added: "One thing I've noticed since I've come into this team, it's like one big family. We are all in it together. There's no one that's gonna be a hero on any one night. We are all gonna work as hard as we can and hopefully get some success along the way."
Tinkler's charges also beat Polokwane City 2-0 in their Absa Premiership opener in midweek.