Hi and welcome to the forum.


Could you elaborate a little on what you would like to spend and what you typically shoot? My initial comments would be:
  • All of the lenses you mentioned should be a very nice step up over what you currently have.
  • 24 mm on a crop body is only 58 degree angle of view vs 76.6 degree at 17 mm, or 83.6 degrees at 15 mm. Those few mm of focal length make a huge difference. So if you shoot a lot of wide angle (I do) I would not recommend the 24-105 mm for a crop sensor camera such as the 60D.
  • If focal length is important, you may want to consider the EFS 15-85 mm. It is optically a great lens over a great range of focal lengths whose primary drawbacks are it's relatively slow aperture and lack of weather sealing. This is my primary lens and I highly recommend it.
  • Image stabilization is great for non-moving subjects.
  • I don't think "L" is going to buy you much more than slightly better build quality and weather sealing over the EFS 17-55 or EFS 15-85. The 60D is not weather sealed, so I think the benefit of a weather sealed lens would be minimal. Others may have more to contribute here. I have one "L" lens, it is great, but the EFS 15-85 and EFS 17-55 are optically in the same category.
  • EFS 17-55 f2.8 is a favorite here on the forum. I think highly enough of the lens tohave considered adding it. Comparing it to the EFS 15-85, one gives you a better focal length range and the other constant f/2.8 aperture. So, which is more important to you? One thought is that you could have the EFS 15-85 plus a 430 EX II for approximately the same price as the EFS 17-55, but the f/2.8 on the EFS 17-55 will give you a thinner DOF than you can get on the EFS 15-85.



Good luck and congratulations on your new camera.


Brant