I believe the beam pattern should be the same, that is determined by the
definition of "E-code."  Whether that pattern is better or worse than
the drop in replacements available for the sealed beams, I will have to
leave for someone more knowledgeable (paging Daniel Stern...)

nate

You can't go wrong with Cibie... I had them... they are great! They last
forever.

Bernard, I have Bosch Euro lights on my 280TE wagon and I love them.
They look good, and seem to illuminate better than the round North
American Bosch lights on my 300DT.  Downside: expensive to replace if
you catch a rock.  And if you're buying on eBay, beware of the
Japanese ones, which have a reversed pattern that lights up the wrong
side of the road.  They don't just pop in, either--you'll have to
change the electrical connections.

Depends which 5-3/4" "Hella or Bosch or Cibie" E-code headlamps you get.

The best headlamps you can put in a W116, period, are these:

http://www.danielsternlighting.com/products/csr.html

I donno. The W116 Euro (flat glass) headlamps look kinda weird, since the
fog lamps are outboard of the headlamps. Performance of the W116 Euro
units isn't bad -- about equal to a decent H4 200mm x 142mm from Bosch.

Performance of the Hella-Bosch-Cibie 5-3/4" H4 units on low beam is rather
middling, though beam formation is fairly good. This is because of the
small reflector active area combined with the inherent efficiency problem
of an H4 bulb: you only get to use 60 percent of the total reflector area
on low beam! With a large enough reflector/lens and careful optic design
this isn't a problem, but it starts being problematic when you're trying
to wring decent performance out of 60 percent of an already small
reflector (5-3/4" round, 165mm x 100mm rectangular...)

Wanna see some objective comparisons?
Take a look at
http://www.torque.net/~dastern/Photometry/575.html

These are isocandela diagrams for different 5-3/4" round headlamp units.
From top to bottom: Halogen sealed beam, Cibie H4 (best of the major-name
units), Cibie CSR (best lamp you can put on a W116).

If you're not familiar with isocandela diagrams, these will look like
random squiggles and lines. Think of it as a topographic or "contour" map
of the correctly-aimed beam pattern. Each differently-colored line
represents the threshold of a particular intensity level, with the color
legend located to the right of the isocandela diagram. The diagram is
plotted on a chart calibrated in degrees. Straight ahead is represented by
(0,0), that is, zero degrees up-down and zero degrees left-right.

To get a mental approximation of the units and amounts under discussion
here:

Parking lamp: About 60 to 100 candela
Front turn signal: About 500 candela
Glaring high-beam daytime running lamps (e.g. Saturn): 8000 candela

The parameters to pay attention to are the luminous flux (total amount of
light within the beam), the maximum intensity and its location within the
beam relative to the axial point (H,V) -- the less downward/rightward
offset, the longer the seeing distance -- stray light outside the beam
pattern and effective beam width (contained within the dark-turquoise 500
candela contour)

I'll discuss the flat-lens Euro units in my response to Nate Nagel further
down in this thread.

DS