I'm looking at it from the perspective of needing SCE to actually be involved. Konami is already going to make three Metal Gear games this generation, and one of those is obviously going to be something like Rising 2 or another spin-off. If SCE was to get involved with Platinum though, then it would be better to work with their own IP or something new in my opinion. If it was absolutely a case of maybe using an existing IP from elsewhere because you can mitigate the risk even further by involving another party, in the case of Konami, I'd think a Zone of the Enders title wouldn't be a bad choice. Since that's a title that would have a tough time existing otherwise. Although with that title's history, you have an uphill battle in terms of the success of the project. So again, I come back to my opinion of using SCE's own IP or maybe commissioning a new one.
As for anything non-Metal Gear bombing from Platinum, I honestly don't think Scalebound is going to bomb. Having a Sony backed or Microsoft backed title is not a bad thing in that respect, if the publishers take the necessary steps to really promote and market the title as one of their notable exclusives. I'm sure Microsoft will push Scalebound and that will potentially help it be more successful than a lot of Platinum titles, if not all of them.
