I have been taking advantage of free shipping codes to buy ammo and collectable items from SMG. Once had a Barska AR-15 scope come apart two years ago and when I finally located the original packing slip, the scope was returned for credit and they honored their lifetime satisfaction guarantee.
My experience in buying military surplus clothing has been similar to the other postings. What they sometimes list as Large is actually labelled "medium" on the garment--in the language of the country of origin. A Swiss rain parka was labelled "Mittel/Moyen" (medium), though listed as Large. They also pro-rate the larger sizes sometimes. My guess is they determine sizes by applying a direct measurement.
One beef I have is that they won't ship a BB/pellet gun to my state. Saw some really cool/collectable pellet guns (military surplus) in their catalogs but it broke my heart that they wouldn't sell me one. Atlanta Cutlery had the same Polish pellet pistol SMG had, but by the time I found out they were sold out. I once had to go to Natchez Shooters Supply to buy the same Gamo rifle that SMG wouldn't sell to me.
However, SMG fills a void left when the local surplus store closed down. I don't need to drive 50 miles (one way) to buy military surplus goods.