I haven't personally played anyone. But i've talked to teh spearhead and ubernick on discord before. I was wanting to know what everyone else has experienced.
I matched with Ninja in a FFA game in the original Reach when he was streaming from his parent's basement. I've played with several youtubers, streamers and matched with some pro players before but that's about it.
Got paired with Mint Blitz in BTB Super Fiesta awhile back. That was pretty cool, and I actually came second on the leaderboard under him so even though we lost I like to think I did him proud at least