It means you are less likely to get cut up for a start. If someone is trying to skip the queue by getting in the wrong lane, they are less likely to attempt to outdrag you at the front to nick your place. Even if they do, you can make sure you aren't in their way when they pull in.
I have noticed people in faster cars tend to drive more calmly... the slowest-performing cars are generally those you see being caned around the town centre by Wayne and Kev.
Convertibles are great, you are aware that everyone can see you and you feel very self-conscious about giving it welly.