I'm shopping for a new sled now. During one visit w/ a dealer I asked about Merc options. He told me they are in fact putting out a 4-stroke that is supposed to replace all of the OptiMax and Pro XS 2-strokes. He didn't have a timeline but made it sound like it would be soon. I went home and did a lil looking on the internet - nothing.
That same dealer told me Yamaha has a serious backlog on SHOs. Demand + some technical issues at the plant are causing this. He was kinda evasive during this part of the conversation. A quick look on other fishing/boating sites revealed a few threads on quality issues w/ some of the SHO powerhead parts. Dunno how accurate this is. Just recalling what I read.
Merc appears to have put everything in to its 2-stroke line. Manufacturing, supply chain, service network, all of it. You'd think the Verado experiment would've spurred a few more developmental efforts, esp after the SHO came out. Good thing. At this point I'm planning on staying w/ a Merc 2-stroke. Sustainment and maintenance won't be issues, even if a new 4-stroker comes out.