Anamorphic lenses vs Zoom

[J.Seb]

I keep thinking "oh, wouldn't it be great to have anamorphic lens to get rid of the black bars projected outside my screen and have a brighter image?"

But then when thinking about the pros and cons, it looks pretty clear to me that it is not really worth it…

Anamorphic lens:
PROS:
- Use all of the pixels available
- Brighter image
- No light spill outside the frame
CONS:
- Very Expensive
- The projector needs to stretch the image (possible loss in quality) and then the lens will manipulate it again. My understanding is that these can only make the image worse, if it all goes perfectly well, it should be just as good.
- The light may not spread as uniformly unless the screen is curved (which are more expensive)
- Pincushion distorsion
- Other optic distorsions - chromatic aberration, rainbow effect?

Zoom feature:
PROS:
- Cheap
- No added distorsions
CONS:
- Loss in brightness

So what do you guys think?