I'm actually slightly fearful that the ZOE collection will have some issues. Perhaps not, but there are hints throughout the MGS collection that concern me.
Basically, when a lot of particles and transparency effects fill the screen the engine does slowdown. Both games try to run the cutscenes at 60 fps and largely succeed, but when effects start filling the screen performance drops. The entire open sequence of MGS2 fails to hold its framerate as a result. It seems like it drops frames in areas that the PS2 may not originally have, in fact.
ZOE2 fills the game screen with even more ridiculous effects on a near constant basis.
The PS2 is extremely well suited for drawing lots of particles to the screen (which is why the MGS2 XBOX port was so lousy, I believe). For ZOE 2 it was already rendering the particles at half resolution on PS2 despite this strength. Even with the more powerful current consoles, an increase in screen and particle resolution and the addition of AA is likely to have an impact on performance. I'm sure it will still be smoother than the PS2 version, but I suspect it will give Blue Point quite a challenge.