They are well engineered because the parts are intelligently designed to place the vast majority of seams in places where they are easily cleaned and moulding gates in inconspicuous places which are easily cut and cleaned without surface damage to the visible faces of the parts. They are well engineered because the parts breakdown facilitates painting of small, complex ships rather bettet than most kits. They are well engineered because the parts don't have ejector pin marks in stupid places that are difficult to eliminate without damage or loss of surface detail.
Lastly, I've yet to assemble two Flyhawk pieces with a less than perfect fit.
I REALLY don't see what there is to moan about. They are brilliant. Try actually assembling one before slating them. Just leave off little steam pipes and ammo boxes if you don't want them.