Well after months of hearing how awesome this lens is I sold my 70-300 f4-5.6
to help cover some of the cost of the L lens!
Thanks to Irish1 I was able to save an extra hundred dollars with a coupon code, along with the canon rebate the total was a cool $1474.00 plus shipping from B&H. Not too bad since my local store wanted almost 1900.00 for it!
Thanks to all here for your great info, it has really helped.