Almost all major tournaments use the 1.02 revision.
To ensure you have version 1.02, the MD5 checksum should be: 0e63d4223b00bd7920dc71579f05a2bc . Step 2: Installing Dolphin or Slippi melee iso ntsc 102 install
The most common method is using a homebrewed Nintendo Wii. Almost all major tournaments use the 1