Hey All,
I am a newbie to DSLR photography. Started taking pics of my son playing paintball. Got advice from one of the top paintball photographers. On his advice, I got the 40D with 70-200mm 2.8 lens. Now, almost a year later, I have two 40D bodies and have added some awesome lenses. I am also starting to shoot portraits, headshots, fashion, and events. Would love to start shooting weddings. I also do indoor sports, theater performances, concerts etc. Though I started shooting 90% paintball and 10% other stuff - now I shoot 50% paintball and 50% other stuff.
Ideally, I am thinking about upgrading one of my 40D bodies and keeping the other as a backup to whatever I buy.
OH - and I have the following lenses: 16-35mm mkII, 50mm 1.8, 24-70mm L, 85mm 1.8, 100mm 2.8 macro, 70-200mm 2.8 (my fave!) and a Tokina 10-17mm fisheye (on the way ) - seemed like a fun lens to have for paintball!
I need your expert help and advice. Here are my questions:
Should I buy a friend's 5D classic for $1100 and keep both 40Ds?
Should I buy a used 1D MK IIn and keep one 40D as back up?
Should I buy a 7D and keep one 40D as a back up?
Just keep my double 40D set up for now and save for my son's college? : )
I welcome and appreciate any and ALL advice, suggestions, etc.
Thanks so much for your help.

For weddings I really appreciate the Canon 1D/1Ds bodies. The AF performance is unmatched by anything else in the Canon line, especially in low-light. The recent 1D/1Ds bodies also have dual memory cards for safety and much better weather seals, as well as very nice battery performance. The 1D MKII or 1D MKIIN have become very reasonable on the used market and they still perform quickly and accurately. The crop 1.3x/APS-H format is also a nice compromise between the larger and smaller formats.

For formals I do like the 5D MKII. While it lacks some of the features of the 1D/1Ds cameras there is no disputing the extra detail you can capture with the best lenses. Your EF 24-70mm, f2.8L USM would be a much better standard lens than it is on the Canon crop 1.6x bodies (like the 40D), and the EF 16-35mm, f2.8L USM II is just a marvelous super-wide, capable of vista landscapes and in a church it's great for establishing the venue.

For theater work the EF 70-200mm, f2.8L USM gives some extra working distance while the 5D MKII gives very nice ISO 3200 and usable ISO 6400, necessary for many theatrical lighting scenarios. The EF 85mm, f1.8 USM is also a wonderful low-light lens on a FF camera. I do suggest the EF 50mm, f1.4 USM over the f1.8 just for more accurate AF.

The 40D is no slouch and I do like mine for candids and family stuff, especially coupled with the EF-S 17-55mm, f2.8 IS USM. Keeping at least 1 - 40D would not be a bad idea at all. Indoors, especially for a wedding reception, you do need a decent flash with an AF assist light. I also highly recommend flash modifiers and I can recommend some DIY modifiers if you wish (ones that I use, of course).

What is a flash modifier?

Flash modifiers:

You can create your own light modifiers (DIY). A couple that I can recommend are:

http://www.fototime.com/inv/908195739C4C0D3

http://abetterbouncecard.com/

Joe Demb also makes an interesting device for sale (reasonable):

http://www.dembflashproducts.com/flipit/

I own a FlipIt product and it works well and is very well made.

A site showing various modifiers in use:

http://www.the-meissners.org/2006-sm...mod/index.html