If it is in good condition, it is probably a very good lens. I know the
Componon-S lenses are very good; I have a 105mm, a 150mm, and a 180mm.

For a given enlarger height, the 135mm will give larger images. I do not
have one of those, so I do not know how even the illumination would be at
the corners, but if Schneider claim it will cover 4x5, it probably will.

Lib,

Either lens will work for 4x5 negatives.  I use a 135mm so that I don't
have to raise the lamphouse as high.  If you tend to make 8x10 and 11x14
prints, this doesn't matter.  But to make a larger print with a 150mm
lens, it will have to be pretty high.

Also the Omega D2 will require the right lens cone for proper focusing.
50mm and 80mm lenses use a flat lens board.  A 135mm lens needs a 2.25"
lens cone (I think).  The 150mm lens needs a longer one (4.5" maybe??).

Also...I nabbed a nice Rodenstock Rodagon 135mm lens on eBay for $22 a
couple weeks ago.  There are plenty of bargains to be found!

pgg