They fit perfectly, leak absolutely NO sound, and sound better than the P5's. I was blown away by the sound quality after changing the tips.
Solution: Comply T-500 <3
Triangular. I almost gave them away, but I thought I'd give them a try with the new tips, and I was very impressed. They even sounded much clearer, and the bass was not muffled like before. Vocals are very good as well. If you own the heartbeats, I seriously recommend you try them with other tips (Comply T-500 worked amazingly well). If the quality persists, I'd say that these sound better than anything I've ever tried.