Differences between uk market sigma lenses and us market?

I am about to purchase a sigma 17-35mm lens from a US based seller for much cheaper than in the UK, thanks to our great sterling rate.





Is there any differences between the UK and US models that I should be worried about?





I've already been assured that this item is not a gray market or parallel import products.





aside from customs yada yada what else should I be concerned about?|||Only thing you should think about is how much shipping cost and import tax.|||There is no difference in UK or US Sigma lens, but repairs or exchange will be expensive, the shipping cost will be high and to wait for longer.