The England international made his first appearance since suffering a knee injury in January, by playing for the Arsenal Under-21 side last week.
"He gives us something different - he gives us pace," Wilshere told Arsenal Player. "I know we've got Alex Oxlade-Chamberlain who gives us pace but Theo gives you something different without the ball.
"I've never played with someone before who times their runs so perfectly and keeps doing it, time after time. It's tough in a game to repeat those sprints 15 or 20 times but he does it, and it's a dream for a midfielder.
"People questioned his finishing before but he's improved so much. He can run in behind and he's good on the ball, he's improved that too. When you get someone back of Theo's quality it's going to give everyone a boost."
Arsenal are next in action when they face Anderlecht in the Champions League on Wednesday.