Tempted to pick this up... Already have collection on PS3 but just like the idea of MGS on the move, such a shame no Peace Wlaker tho it would make perfect sense to have it on there as it was built as a portable game!
Honestly you have to play it, so much gameplay ridiculous how many missions there are its MGG but with RPG elements :P Co-op is also done well and can be hilarious.
In short its very important to the series as Ground Zero is pretty much the follow up of PW.
umm does this game franchise is hard... ive never been played any metal gear game not even on my psp but ive seen this game on psn as 20$ for metal gear solid 3 and 2 what do you think should i play first? i want the easier one to try out first
10°
30°
20°
40°
Ad 
40°
And the collection is great on Vita, you should definitely consider it.
In short its very important to the series as Ground Zero is pretty much the follow up of PW.