I am looking into purchasing a 2005 G35 Couple with 20000-30000 miles. Do they run strong and last well when reaching 100000+ miles?

Yes they do last long.
But they are expensive to maintain and fix.

Like any car that is taken care of. Most Japanese cars they have this look on their plastics. They look pretty wore out after few years. Is a cheap kind of looks.

dey can last 500,000+ or more...very
reliable.and nice looking