There seem to be two kinds of IFR pilots in the world: the ones that think nothing of SPIFR if properly trained and qualified in a properly equipped helicopter and the ones that cannot conceive of SPIFR and will pull out any excuse to dismiss the concept.
Meanwhile manufacturers don't build an IFR medium without certifying it for SPIFR.
Spinwing you're drawing on an inside straight. All kinds of things would have to go wrong at the same time, including coincident weather, for the Single pilot to work up a sweat. The standby HSI/ADI should have a Nav input anyway.
All the 139's I've seen have two screens on each side, with an miniature EFIS standby in the middle.
Charon