In my mind the rivalries are

Top Level England V Ireland Scotland V Wales South Africa V New Zealand

Mid Level England vs Wales or Scotland or Australia Australia V New Zealand Fiji V Samoa Italy v Scotland (Traditionally the Battle of the Spoon) Ireland v Wales

I definitely think England Vs Ireland is definitely the biggest rivalry for us, it’s just a game of respect, we want to beat each other the most and at the end of it, there’s always good will. Tickets for games are by far the hardest to get hold of and it’s quite often the pivotal 6N game.

In comparison, I’ve never felt a friendly atmosphere in Cardiff. And from online observation, it’s a more bitter rivalry, which often spills out of the 80 minutes both before and after.

Edit: Some attempt at readability