When we get to the store, they try to give us equipemnt we didn't order (we ordered 1 dvr box and another box and a wifi modem.) We ended up leaving with the right boxes, and not Wifi. That, of couse, can't be picked up in store. It can either be mailed to you, or a tech can bring it. My mom opted for it being mailed here, and that went over as well as getting the original items went.
During this process, we were regularly lied to about the items being shipped out and them working.
Oh and a bonus. The 2nd cable box we got only gets TNT (it was NJN *new jeresy network*) so it's not worth having, but not worth dealing with comcast again to see if we can fix it.