Utter Bollox.
APR Piston is a single diameter and Autotech/KMD etc have a stepped piston. The step in the piston forces fuel past the energised seal as a liquid doesn't compress and it has no where to go.
It's just a question of how long your seal lasts. Some last 5k miles mine lasted 50k miles before i replaced with APR
Utter bollox it may be but the APR is a rip off.
If it's assembled correctly as per instructions in a clean environment then the 50k miles is available.
What are they £600-£700.
Loads of people have Autotech with no issues and I would buy again.
You could buy it all twice over and then you have all new again in regards to a 50k APR!
Just my opinion but the APR seems hyped up and over priced.