These things were Beta tested for over 2 years with improvements and upgrades made along the way. While you may still not be happy with the product, to suggest that they were thrown out there without significant testing is just not accurate. FWIW, I was an early Beta Tester and all of the issues we saw back then were addressed before the product was released to the public. As subsequent issues arose, they were addressed in the 2nd generation version and wet-side upgrades (all very well handled IMO).
I currently run 6 MP40's that are either 2nd generation or upgraded versions and have not experienced any problems with them at all. The MP 10 I just received looks to be an even further improved version of the pump.
If you are happy with maxi-jets and Korallias just stick with them, because the only other high-end powerheads are Tunze's and every single one I have ever had has ended up in the trash bin after an impeller exploding or seizing rendering the pump useless and not capable of repair. At least with the Vortech's if they stop working the repairs are quick and easy.