To the contrary. The KDE motors are excellent. They are powerful, yet efficient. They have quad bearings, run really true, and are very well balanced. The shafts come with flat spots, although I have had to extend the flat spots on some of the shafts. They don't require any maintenance; no need to re-lube the bearings after every 6-10 or so flights.
Of the KDE motors, the KDE-495 is the more commonly used for 700 size helicopters on 12S. I believe the lower Kv motors like the KDE-395 and KDE 295 are better suited for 14S and 16S applications or particularly low head speed applications.