[Ryephile]

It's not likely the production car will have SLA, even though I'd prefer that. What you see appears to be a brace to hold the strut in position since there's no strut tower sheetmetal.

McPherson is probable because:
A) the Subaru press release said so
B) the McPherson struts shown in the see-through concept wouldn't be used on an SLA [short/long arm] suspension setup. SLA's typically use compact coilovers that aren't designed for lateral load-bearing.
C) the proposed upper control arm angle would result in an asinine camber curve
D) the engine shape dissuades upper control arm mounting points
E) McPherson strut setups are slightly cheaper, and cheap is a big priority
F) hubs and control arms could be easily parts-binned from other Toyota/Subaru cars, since they both use plenty of McPherson setups, thus making the car even less expensive.

That's my deduction.