Enjoy your lens. The greatest advantage of your lens lies in the fact is lightweight and offers excellent L quality.
I have the much heavier F2.8 Is version. Sometimes it is so heavy (after hours of use) I am now thinking of getting the F4 version. I do not really need the F2.8 all the time, i do day photography most of time. I think the extra weight is a pain on my neck. It is the "IS" that entices me get the F2.8 in the first place.
Now that there is a F4 (lightweight) and IS (hand shake reduction) version, it proves to be VERY tempting.