This party is the...

Have I guessed them correctly?

1) This (party ) is the best thing ever! (right now).

2) That (party ) was the best thing ever! (The party has just finished or it finished some time ago).

3) This (party ) is the best thing I could ever ask for! (I have just been surprised).

4) That (party ) was the best thing I could ever have asked for! (I am talking about yesterday's surprise).