darth mollusk those shots are really great seams like a pretty awesome bang for buck lens
also out of interest what bag do you have that fits that in? i dont think my current bag will hold it
I was going to get a gura gear but they have extortionate shipping charges
thanks - those results are relatively typical for this lens, on the 7D it certainly rivals the canon equivalents (70-200 and 300 2.8 ). pwp is right - it is a beast, weighing in at nearly 3kg, but consider that you get a sharp f2.8 at 300mm with the ability to zoom back (it's surprising how much you'll use it). I bought a blackrapid strap for it, screws right into the tripod mount, so the lens sits comfortably at my side. My arms certainly will burn out relatively quick (I weigh in at a slight 80kg as well) - but the lens is only up for 20-30 seconds at a time. I find I'm slightly quicker without the tri/mono-pod (depends on the situation of course). I had it on the tripod today to shoot my wife running an adventure race... a good example where f2.8 was essential for low forest light and the zoom got me twice as many shots.
I bought the f-stop sartori - absolutely brilliant bag, relatively expensive, but you get what you pay for. geez - sigma and f-stop should be sponsoring me for this. the Sigma 120-300 fits vertically, attached to the 7D body, inside the large ICU along with my tokina 11-16, 430ex, extension tubes, tele-converters and the 50mm 1.8.
Not sure about the actual focal length - whether it's less than 300 or not? keep in mind also that Sigma have (at least historically) a reputation for suspect quality control - so there may be a risk that you'd acquire a bad copy (likely low - but be aware). for that reason I bought it new and tested it thoroughly - my copy was sharp.