But they have a fight strap, so they must be authentic, right?
Having bought from overseas before (once and never again), the quality is not even close. The lettering is often lopsided and is stitched crooked. The jersey material is similar to that of a cheap pair of running shorts. Numbers are always the wrong size, often using 10 inch numbers instead of the proper 12 inch numbers. From what I've seen on the Penguins' jerseys, they use a yellowish color that is far from the actual gold on the authentic jerseys. The logos? They are often the wrong shade of color. I won't even start with the lack of proper sizing... eh, ok, I just did. The sizing is very inconsistent, to where a 52 fits like a size 46 and vice versa.
But if you want to order these "authentics" that look like a 3rd grade art project, then by all means go for it. I would rather have one authentic jersey of a player that played for my favorite team for 20 games over a decade ago then have a closet full of these "authentics" that people brag about as a major collection.