You can relive Halo: CE and Halo 3 right now...

With a decent modern PC and a copy of Halo: CE you can play CE multiplayer to your heart's content. The only problem with Halo 3 these days is that the population is abysmally low. Seriously, if a whole lot of people just put Halo 3 into their Xbox 360 and started matchmaking then the same old experience would be there. Just a thought.

You wouldn't be reliving glorious times in halo playing a broken pc game of halo. I remember the best time of halo pc they were amazing but it was clear they did not continue to patch thee game very well, just became a mostly broken lagggy mess. Most matches are just races and rocket launcher only games,

Halo reach still have good numbers considering how long it's been out more than twic what halo4 has.