Sigma 17-70 -- is this normal?

I just received the Sigma 17-70 f/2.8-4 DC MACRO OS this afternoon. I am thinking I might have a bad lens but wanted to check to see if this is normal. It was difficult getting it on the camera--not a smooth fit by any means. Also, when I gently shake the camera (not that you should do this), something inside the lens is rattling. It also sounds much different than my Canon lenses when I take a shot. The shutter is loud.

Is all of this normal? Or should I just send it back?

Ive had one for years and never heard anything inside of it. And mine goes on and off just as any other lens. But thats just my copy, be curious to know what others say though.

not normal, I own one and it doesn't have issues like what you're describing.

Thank you. It's going back tomorrow. Darn, leaving on vacation soon so I won't have a good walk around lens. Oh well, I love da birds!

I should also mention that I bought the lens from Amazon. I think the lack of padding may have contributed to the damage. They threw the lens box in a shipping box with those air pads but there was nothing protecting the top/bottom of the lens box. Perhaps I'll order from Adorama when I get back. They do a better job of packing. My first/last lens purchase from Amazon.