Um, you do know that 10mm x 1.6 is waaaaaaaaaay wider than 17mm x 1.6 right?
Yup.. thats make the 17-40 into 27.2-64 But 17-40 also a wide angle lens but on a FF but on a crop still alright. If he really dont feel the wide that wide enough then get the 10-22 thats make it to 16-35.2. ;p