[MultipleParadox]

The thing is (at least, that's my opinion on this), you cannot buy boots and such online, unless you are ready and have certitude that you can return/exchange them.

Boots, especially for airsoft or similar activities, have to fit you well and you have to be comfortable in them or you'll swear your day away and not enjoy anything.

All makers don't make their boots the same way and all, so even if you'd have certitude you normally use size 10 boots, company A's boots might fit better for your with 11, or you might be better size 10 for company B's boots, or 9 in another's. Then you sometime have width measurements. Some makers will make the same sized boots in different width to accomodate different feet. Which one you take? Take a guess and find out you can't wear them? Bad idea in my opinion.

Also, one guy might swear only by Swat Original because they're the most comfortable, but you could find out that for you they're more like a torture apparatus, and vice versa.

If I have a recommendation to make, it's this one:
Go to your local outdoor store, or surplus store, and try them all. When you fell really comfy, buy them and enjoy.

Of course, make sure you buy quality if you want them to last. Vibram soles are often recommended (they got a lot of attention recently as I recon; It doesn't mean that non-vibram is not good, it might be the same or better or not). Goretex membranes or similar is a great plus, as it'll keep you dry if you get in water and such.