Hello, was wondering if anyone tried or have this lens yet? Went to B&H but didn't have it in store for me to try it on. Wanted to know how this compare to sigma's 70-200mm f/2.8 II DG Macro HSM & 70-200mm f/2.8 DG Macro HSM. which I haven't tried either. just in case , I'm using it on 5D. Any comments will do. thanks in advance!!