Missed this thread when it started, because I was busy on Cygnet, an Owl Class boat built by the said Mick Sivewright. They will of course have different modifications of the fit-out, but Cygnet is extremely well-designed, and has been over most of the system in the past five years - perfect for me and my dog, but, as I say much to Mrs Mac's annoyance, too crowded when she and her dog join us. The (second) engine is a Vetus, but with the original water-lubricated stern gear. I just love it, and have met several others (all types of owl) equally loved.
Mac
Edited to say that even if the Gas fire was non-compliant, it certainly wouldn't put me off if everything else ticked the boxes. Replacing it with a small solid fuel stove wouldn't be difficult, and probably a lot cheaper to run.