17 you have the best mania main event ever as far as match quality. Plus other really great matches as well.
3 you have Hogan vs Andre which was terrible, but the historical significance can't be beat. The only great match was Savage vs Steamboat, but most other matches are decent to good. No really bad ones.
For me one day I'm saying 17, the next I'm saying 3 just based on history and lasting images. To this day that crowd and Hogan slamming Andre still gives me chills.