I went a half size larger due to recommendations and it made for a perfect fit with my socks that I wear from Under Armor and Smart Wool for boots.  Wear them at work in warehouses, so I am on my feet all day and need very comfortable footwear, and these "Hi-Speed" boots fill the bill.  I have worn Oakley Assault Boots in the past, and I think the Danner Melee will definitely out last them based on quality of materials and construction.  Used this boot to replace two pairs of shoes that I had worn out, and I am very impressed with them.  The color is very low key and they blend in very well with street or work wear.  An excellent boot that is worth the cost of admission!