After my 7D and 17-55mm F2.8 IS USM lens went through the Upper Antelope Canyon falling sand abuse I decided to send in the lens and camera body for a professional cleaning and check out. I shipped them to the Irvine, CA Canon service center last week. I got them back this morning and I'm impressed.
On the lens they did a great job cleaning it inside and out. It looks like new now. Sand had gotten into the focus ring assembly and they didn't even mess with trying to clean it. They replaced the entire auto focus assembly with a new one. I'm sure that it is cheaper for them then spending the tedious hours it would have taken to clean the intricate parts but the result is my lens is back in tip top shape and should be fine for years more of shooting. Yeah, someday I need to step this one up to a better sealed L lens but for now the optics in this lens are great.
On the 7D camera body they also didn't mess with cleaning the top control wheels that had sand grit in them. They replaced the entire upper control plate on the camera so all my top controls are now new. They also found a problem (not sure what) with the main mother circuit board when they ran their diags against it and replaced it. Then cleaned the sensor and mirrors and the rest of the body. It too looks and works like a new camera now.
This wasn't cheap, it cost me almost $400 for both the lens and camera but it was worth it. Next time I will protect my equipment better when in ugly conditions.
Just sharing this to let folks know the Irvine Canon service center does nice work and I'm a happy shooter again.