I don’t think I would agree that mosfets have proven to be more durable. Good radio techs and manufacturers have figured out how to make them work but over all they suck. I’ll take any radio that’s dual 1969’s or 2312’s over mosfets. Just ask some RCI n2 and n4 owners how many times they have smoked all their mosfets. And we won’t even talk about the RT1 junk.
I have a book written by Lou Franklin. In it he tells a story where he met a friend for coffee or lunch. To prove a point he parked his car and unscrewed the coax from the back of the radio. He then put a rubber band on the mic to keep it keyed up while they were inside. He came out later and reconnected the coax, the radio was fine.
I have not used a new hg1969 myself. Comments I have seen on the forum say they seem to work fine but do a few less watts compared to the Mitsubishi part. I’m glad we at least still have options at this point.