It was the first sniper I did to complete all of the challenges and it is a one-shot-kill 95% of the time like Meow said. I run around with sensitivity on 10 and pick people off close range. I love it but I am sure I could be better with a semi-auto though.
I used the PTRS in COD5, used R700 in COD4 and Intervention in MW2
I find that theres so much resemblance between the guns, it just seems natural to use them.