Re: It's time for an airshow!!!
The reason why you almost ended up with a cheap, off brand lens with your camera kit, is because you bought it from a reseller that creates its own packages. Sunshine Electronics seems to have a mixed review status, with some people reporting a good experience and some a bad experience.
The camera store that you went to gave you good advice, if you own a Cannon camera and want top quality glass, buy Canon lenses. The same is true of Nikon - I own Nikon bodies and shoot with nothing but Nikkor lenses. That said, Tamron is a trusted name in aftermarket lenses, as is Sigma.
It sounds like to me, that Sunshine got you on the phone to upsell you on a low priced package that you saw on EBay or elsewhere. That is pretty much their standard drill. As long as you get something that you are happy with, for a fair price, this isn't the end of the world, but you have to be careful with many intenet resellers. Others, such as B&H photo, have very good reputations.
One suggestion that I would make, is to contact Canon to check the serial number on your camera. This is important because all of the major brand names make cameras for the U.S. market, as well as cameras for other markets. What is crucial about the status of your camera, is that those that were manufactured for sale outside of the U.S., will not have a warranty that is honored in the U.S. These cameras are referred to as gray market cameras. They are often sold by the mail order/internet resellers at prices well below what is offered for the U.S. cameras. The deals offered seem to be good to those who don't know any better, but can end up becoming a serious problem if the camera has any issues.
You may or may not have a gray market camera. From what I have read, Sunshine sells both. If it turns out to be a U.S. camera, you should be ok.
BTW, the spot that you saw in all of the photos was probably dust on sensor inside of the camera. One trick to avoid such problems is to always make sure that the camera is turned off, whenever you remove a lens. While there is some disagreement as to whether or not this is necessary, some say that leaving it on will attract dust to the sensor because it has a static charge when powered up. If you read your owner's manual, however, you will probably find that Canon recommends that you do so.
As a former aviator, and air show nut, I really enjoyed seeing your photos - they are very well done!
