Sorry but im looking at the moment for an m35 and am having HEAPS of options with warranty, Most places dont mind where its serviced, so long as its done every 10,000kms or 6 months (which ever comes first) this is a big advantage for me because here in canberra there are no car importers so yeah
Nagoya motors and GT High Performance are 2 that spring strait to mind, not sure about northshore imports but just ask, most dealers will do 5 year warrantys for free so yeah.
Just my 2C's
Cheers, Michael