Jaeger Precision's initial external testing of the WellPro PPK20 Gas Blowback Rifle  showed positive results, noting that the hop-up performance was superior to the AK-12 model and was easily adjusted with a 2mm Allen key.

However, the review was dominated by significant issues with the rifle's gas magazines. They repeatedly failed to accept or retain a full gas charge, leading to a quick loss of power and snappiness during firing. This made hitting targets reliably difficult and hindered consistent full-auto performance, with the rifle chronoing between 238 and 240 FPS on a .3g BB.

He states that the heavy, poorly manufactured magazines with subpar inlet valves are the "Achilles heel" of the platform. He plans to modify them, possibly with Tokyo Marui purge valves, in an effort to improve reliability, and expressed hope that Well Pro will release better magazines with a future PP19 model.