I don't know if you have been duped, but can say I have used thousands rounds of Winchester Q4318 NATO 9MM over the last ~20 years. More recently, have shot a fair amount of IMI 124 grain NATO ball. Chronographed these two versions of 9MM NATO in a variety of 9MM pistols, revolvers and in the Marlin Carbines. The Winchester usually runs mid to high 1100s in ~4" - 4.4" barrels, 1200+ in 5" guns and around mid 1300s 16" barrels. The IMI NATO consistently produces about 3-5% more velocity than the Winchester NATO in the various guns I've tested both in. I consider both to be excellent, and they have in fact become my favorite types of 9MM ball ammo. Consistent velocities, both sealed at case mouth and primer, both have crimped primers,etc. The Winchester primers are much more heavily crimped, and I've had to remove the crimp prior to reloading. The lighter IMI crimp has not required removal prior to reloading. Both cases have proven very durable for reloading.
BTW, I've chronographed several different types of commercial 124 grain +P ammo in a variety of firearms too. The 124+P consistently produces velocities higher than the Winchester 124 NATO, but the IMI 124 NATO demonstrates velocities similar to the 124+P.