Chicharito has appeared in all three of United's competitive matches so far, netting a debut goal against Chelsea in the process.
"He's made a big impression," Giggs told ManUtd.com. "He's still learning the game, not only on the pitch, but off it too. He's a bubbly character and he's great to have around the dressing room.
"It's been a lot easier to get to know him because he speaks perfect English. He joined us on tour which always helps a player settle, and we saw first hand how big he is in Mexico. He looks a great acquisition, both on and off the pitch."