How do you know which crack to use?

[Machina]

I just wonder... if you have 3 or 3 cracks for the same game, and version, which one to get?
like UT2003 has 2 cracks, one is 70Kb and another one 300K or so! Does the size matter? It seems the 70Kb lets me load the game faster, but I don't know...
In which order does it go for best crackers?
I think
1. Myth
2. Deviance
3. FairLight
4. gimpsRus (or whatever)
5. Class
6. BullsEye
not sure about spelling