Are Apple Macs Good For Gaming?

http://store.apple.com/uk/browse/home/shop_mac/family/imac?mco=MTM3NDk0NjU I found some good Macs on Apple.co.uk but I dont know if there good for games such as The Sims 3 and Expansions. Please help and give me some links, I dont care about price and I know Sims 3 Specs. Thanks.