Let's put it this way, Peace Walker was arguably the best game on PSP, but Solidus and a couple others here have a hate boner for it
I didn't play on console but it was definitely the best game I ever played for PSP hands down.
And it's probably way more relevant to the canon than MGS2 and MGS4 right now.
Dude, even pturtle doesn't want to reply Peace Walker (but, I think his reasons were for the gameplay and level grinding) . I enjoyed it for the gameplay, co-op and online - like I said a million times before. The gameplay was fun, but the storyline and regurgitated "Peace" theme was atrocious and patronizing.
I'm not sure what the story elements are for MGS V. But, if it has anything to do with the creation of the Patriot satellites (and nanomachines to suppress language and thought), I'm sure it will tie into MGS 2 and 4 in some way. It'll be disappointing if it doesn't, since this game is supposed to close the loop on the entire timeline.