The O's sit on top of League One with a 100 per cent record following Saturday's battling 1-0 win at Stevenage.
It is a far cry from last term when the O's were rock-bottom of the table after losing their first four games, although they rallied to eventually finish seventh.
Slade said: "It's a wonderful start for us, though it has only been three games, but the momentum and spirit of the camp is very, very good and they all work very hard for each other.
"You have to have a certain mind-set when you come to places like Stevenage. You have to be strong, both physically and mentally, and we were."