The HD collection includes Metal Gear Solid 2: Sons of Liberty (with additional content taken from the 'Substance' reboot) Metal Gear Solid 3: Snake Eater (Including the NES versions of Metal Gear and Metal Gear 2 in the menus) and finally Metal Gear Solid: Peace Walker ported over from the PSP. MGS 2+3 are the same as their PS2 counterparts but with a little extra content, nothing too big to be excited over but a welcome addition to the original games. The HD is very noticeable when comparing to PS2/PSP and makes all characters and areas look fantastic with colours and graphics being sharpened to make the experience more pleasurable. Peace Walker Looks great in HD too and has improved controls now that its come to the mainstream consoles. The PS VITA version of the MGS HD collection does not include Peace Walker, but is often cheaper than a PS3 copy and can still be bought separately on the PS Store. Overall these game are just like you would remember but with better visuals and extra content..
I favoured the VITA collection over the others because I couldn't resist having Metal Gear Solid with me anywhere and anytime.
This an Excellent example of what a HD collection should be and is fairly cheap to pick up now that we are in 2015. If you enjoyed Metal Gear Solid back in the day or, like me, wanted to have it on the go, then you cant go wrong with this collection.