-It appears that Metal Gear Solid 2 is the Substance version and is intact.
-Metal Gear Solid doesn't include the VR Missions disc nor is it like the Japanese Integral version, it seems.
-No inclusion of The Document of Metal Gear Solid 2.
-Metal Gear Solid 3 doesn't include disc 2 or 3. (So the MSX games Metal Gear and Metal Gear 2: Solid Snake and some extra modes are missing!)
Just a heads up. If you're new to Metal Gear then instead of the Essential Collection I suggest you look for...
-Metal Gear Solid
-Metal Gear Solid: VR Missions (aka Special Missions in the PAL regions)
-Metal Gear Solid 2 Substance
-The Document of Metal Gear Solid 2
-Metal Gear Solid 3 Subsistence
...not to mention the other Metal Gear games the pack didn't begin to include in the first place!
Hope this post helps some people!
P.S. I acquired Metal Gear Solid Mobile for my mobile device today and it looks pretty cool! (I have Verizon and your service may vary.) It seems to be a non-canonical spin-off of sorts rather than a remake of any of the existing games.