I posted a similar question on the Sony SLR forum but I realized that I may get more 'experienced' answers here.
So here goes:
Because of design constraints I've gathered that E lenses while okay for the most part do not perform nearly as well as full-blown ALPHA lenses do.
There have been several very enthusiastic reviews for the the f2 24mm ZA lens (Photozone and SLR Lens and Camera review) with expressions like "one of the true marvels out there" and "exceedingly sharp" and "If there is such a thing as perfect wide angle lens, Carl Zeiss Distagon T* 24mm f/2 ZA gets as close to that definition as one can imagine."
On the other hand, two reviews for the f1.8 24mm Zeiss "E" lens (SLR Gear and Steve Huff) while positive for the most part seemed a bit muted or riddled with faint or backhanded praise with expressions like "maximal sharpness is achieved at â/4, where it's not quite tack-sharp" or "While it is not clinicaly sharp, it has characterů and to me, that is way more important that hyper sharpness".
The variable is one of the 24mm Zeiss lenses is mounted on a NEX 7 body with nothing standing between it and its 24mm sensor while the other 24mm Zeiss has to contend with a lens degrading pellicle (not sure about image but lens performance is curtailed by 1/2 to 2/3 of a stop).
So I was wondering, with equal sensors, whether the trade-offs in IQ of an NEX 7 with an E mount 24mm f1.8 Zeiss lens and no pellicle to hamper lens speed will be better, equal or worse than the IQ of an a65/a77 with its 24mm f2 Zeiss ALPHA lens.