I've seen a few Islanders with all the toys such as RMI's and HSI's.
Operating unpressurised is no problem apart from when you go down to the mountainous bits of Europe. We had lots of problems with a route between Marseille and Paris because of the Massif Central. Whichever genius management pilot had put the route together had forgotten that the single engine drift down alt for a shed was usually around 4-5,000' but had planned the flight going over ground where MSA was 8,700'. You didn't really notice at night, but on a daylight trip, it was pretty startling!
Cue lots of swearing when we first started flying it and lot's of poring over charts to find a way around. This was the only time we stuck to the flight planned route rather than just taking a direct routing when offered. French ATC sounded very surprised when we said NON every night! Until we explained why.