I personally liked act 4 the best going back to shadow moses was awesome. crying wolf and vamp boss fights were sweet but what made act 4 the greatest was driving metal gear rex and the rex vs ray boss battle

my order for how good each act was

1. act 4

2. act 1

3. act 2

4. act 5

5. act 3

damn thats a hard question. I'll have to split into two groups: the best act story wise and the best gameplay act

gameplay:

act 1.
act 4.
act 2.
act 5.
act 3.

story:

act 3
act 2
act 4
act 5
act 1

they're all so damn good its hard to decide. Best game i've ever played that includes final fantasy and zelda...

1. Act 4 (loved going back to Shadow Moses)
2. Act 1
3. Act 5
4. Act 2
5. Act 3

Hard for me to break the game down into favorite acts. I just like the game as a whole. If I had to, I guess I'd say act 1. I just had a smile on my face thinking "Oh my God! I can't believe I'm finally playing this!"

Gameplay
1) Act I
2) Act II
3) Act V
4) Act IV
5) Act III

Story
1) Act V (and the epilogue)
2) Act IV
3) Act III
4) Act I
5) Act II

Gameplay:
1. Act 1
2. Act 3
3. Act 2
4. Act 5
5. Act 4

Story:
1. Act 5
2. Act 4
3. Act 1
4. Act 3
5. Act 2

Act 4, Wowee, that was the most amazing gaming experience I've ever had. If I hadn't played MGS back in the day, the impact wouldn't have been the same at all.

1. Act 4
2. Act 5
3. Act 2
4. Act 1
5. Act 3

Act 4 ftw!!!!!!!!!!

1. Act.4
2. Act. 5
3. Act. 3
4. Act. 1
5. Act. 2

I'm in the middle of my second play through so I can't say for sure yet, but I think I would have to say Act 5, the boss battle with the last BB and references with MGS1 after the boss battle and just the pure excitement I felt knowing I was closing in on the end, and the final boss battle was just amazing. After that it would be 4, 1, 3, 2.

Gameplay:
1.) Act 1
2.) Act 2
3.) Act 5
4.) Act 4
5.) Act 3

Story:
1.) Act 5 (and ensuing epilogue and mission debriefing)
2.) Act 3
3.) Act 4
4.) Act 1
5.) Act 2