I am very astigmatic and when best corrected, come in at
something like 20/40 or 20/35.

For several years I've had progressive lenses which I carry
with me.  I use them for driving, walking around, museums,
and the occasional small amount of reading one does while
sitting and waiting for something.  When I first got them,
the optician made a few different pairs before he found one
that, as he described it, had the right ratio of distance,
midrange and reading.  If I remember correctly, he said that
some progressives are made with a larger midrange distance
while others have a smaller midrange.  The ones I have been
wearing successfully are about 5 years old and are Varilux
Comfort lenses.

I have a separate pair of reading glasses which I use at
home.  I also have a separate pair of progressive computer
glasses that go from screen distance to reading distance only.

Now I need new glasses and I'm beginning to ask questions of
a few opticians.  I've been told that Varilux Comfort lenses
provide very poor peripheral vision and that there are other
lenses now that are superior.  It is true that my Varilux do
seem require that I center myself pretty carefully or things
go out of focus.

Zeiss lenses have been recommended as being optically
superior and providing more peripheral vision area.  Is this
true?  What are the differences between the various brands
of progressives?

And, is it true that some brands give a greater height to
the midrange than others?

Since my lenses, with ultra thin and anti glare etc. are
almost $500, and I need to replace both my everything
glasses and my computer glasses, I'd really like to
understand how to get the best lenses possible and what's
true and what's just hype.

TIA

Louise