I don't recommend the EOS 1n. I have had 2 of them crap out on me with very little usage. Was the shutter every time. The EOS 3 had been my work horse for quite a long while.
Well, I don't recommend the EOS 3 at all, but the EOS 1N. Globally, only a very small number of 1N bodies were affected by a shutter fatigue problem (failure <6,000 cycles) and Canon replaced affected shutters in serialised cameras free of charge between 1995 and 1998. There are a huge number of 1N cameras still in use (a local camera group counts 5 among their Canon users), with the only routine service now being replacement of the internal lithium button cell (not user-serviceable) that maintains system settings such as Cf, drive, ISO, mode, etc., etc., when the main power source is removed. The lithium battery was said decades ago to require service replacement after 5-7 years. Many are still chugging along after two-plus decades!
My trusty, ever-ready 1N+ PDBE1 was bought in 1994, is still in-service after many hundreds of rolls (back in the day when Ektachrome and Kodachrome ruled), and will be used this weekend in muck weather, as is customary.