I bought them from my local Sports Authority, and tried them out for first time. They didn’t have a label Extra Duty, but the small printed “ITF approved” logo assured me that they should be a quality ball.
Right from the beginning they were a little bit depressurized and felt slower and heavier... which is actually what I like since the Penn ATP Masters is my favorite ball. I didn’t notice them being “lighter” and “smaller,” as some posters mentioned. Flying through the air, I thought I could see a wobble, so they might’ve been slightly oscillated. Also as mentioned, they fuzz more and have more texture on them… it reminds me of a poorer quality Wilson US Open ball, which has just as much texture but retains its playability and pressure longer. I checked them out several days after using them; they had lost a lot of pressure… more than the Wilson and Penn extra duty after being used.
The good part is 4 balls per can, but nevertheless, from one-to-five scale, I rate it 3. OK... maybe 3.5, since Head makes nice Prestige frames.