Agreed, for so many years I thought that "the way to go" was an I/O but then the realization of having the engine taking up floor space and STILL having the "outboard" hanging off the back. I'm still trying to figure out why some having 5 or 6 outboards on their boats, could it be the "Bass Tourney" mindset of the faster boat wins
The only way an I/O is the way to go:
boat is old enough not to have complex and expensive cat converter exhaust
owner knows and understand GM small block engines, can deal with difficult access and extra maintenance required by the I/O design and can do much of their own work
Any other situation such as owner doesn't want to or can't do own work, owner lives in a climate with freezing weather and has to winterize, owner wants smaller boat but with enough space inside, the outboard wins.
Yes it cost more initially and sticks up in the stern, and you don't have a true swim platform in most cases. But to me, I honestly can't see buying another I/O for myself, unless its a cruiser style boat, with a big wide open engine compartment, easy access, etc.