Parts availability and prices.

Engines and transmissions easy to get parts from stuff that's stateside.
Its all manual so very few issues.... everything else, when stuff does break, very hard to get parts. All the old cars were grey market so you cant just walk into a dealer and get parts, sometimes they have to call MBUSA and source parts direct from Germany. Have had to do that more than a few times. Depending on availability , it can be anywhere from 5-7 business day (in stock, just needs to be shipped) to interstellar galactic back-order 3-9 months (available, but needs to be built from scratch).