Lars,

Just as a warning Canon rates the life expectancy of the shutter on the 50D @ 100,000 actuations. I bought my 1Ds Mark III brand new from B&H and it's rated at 300,000 actuations and with less then 10,000 actuations had to have the shutter replaced. I am very careful with my equipment (specially anything that costs that much!) so it was not any fault of my own. Luckily it was covered under warranty but if you buy it used you won't be so lucky. It probably is a rare case but they don't warranty it to 100,000 thats just what they expect it to get from testing. Not to discourage you just giving you some real world experience I had with even a pro level camera you have to expect the unexpected.

Fred~