Originally posted by hedpe
what is TYC? I've never heard of them before...
but whats the main difference between bosch and hella?
TYC is a Taiwan supplier of "OEM-Like" replacement parts for cars, not just Mercedes. Body shops will use "OEM-Like" parts in repairs to keep costs down. They are drop in replacements for OEM, but they don't have the "heft" or "feel" of the Bosch units, probably from differences in the manufacturing materials and process.
There may be a slight difference in the glass used in the Bosch versus the Hella. Some have said the Hella glass is slightly darker than the Bosch, which may be the result of the lens cut pattern or the reflector shine.