Horrible.
The system itself is bad, a hell of a lot worse then H3 (which is great except for that it keeps putting forward the same darn maps). I’m fed up with power weapons and it seems everyone online is a scrub. My internet isn’t doing that well, so I have stopped playing Halo 3 because I keep lagging horribly.
I hate the fact that game modes (elite slayer, slayer pro come to mind) do not have their own playlists.
Power weapons are never an issue on Halo 3. It’s just on Reach where every friggin game mode has easy-to-grab power weapons. And playing the same maps gets really annoying, so is the constant black screen issue I get all the time (when someone quits the game, but that doesn’t happen all the time when it occurs).
And the pysche profile and search options are worthless as of now with their current options.
It’s not as bad as you make it sound. I play Reach a LOT (took one profile to Inheritor and another to Legend so far). I’ve been playing it since the day it came out.
If you’re getting black screens often it might be you. You said your 'net isn’t so good yourself. That is a sure sign. Maybe you shouldn’t be on there messing up everyone else’s gaming experience, huh? 
And I still go back and play H3 from time to time. The lag is far, far worse there. It’s horrendous and always has been.
Wanna’ know what REALLY sucks? Not having regional matchmaking. I was in a game on Sword Base the other day where my team were all Americans and on the other team there was a Mexican, an Australian, a New Zealander and an Italian. :o You should have seen the freakin’ lag, man. I was going up the blue lift 5 times. One time I went up it 3 times and came down 5 times, which resulted in reaching terminal velocity and me committing suicide on the floor of the atrium. LMAO! Or running along at the top of red lift then teleporting down to the shotgun room. Holy crap!
These laggy matches could be fixed with a half hour of work in coding. Then it’d be all done.
To be honest I was raging when I made this post.
My internet is actually good, I just couldn’t figure out why I was getting so much lag on Halo 3 and occasionally Reach. I’m glad i’m not the only one who thinks it’s server-side (H3 mainly).
Yeah, I agree, matchmaking has so many potential options that are not implemented (and some things I personally believe need to be fixed), but it’s decent as of now I’d say.
Lag has created some pretty strange moments for me. For instance, on Boardwalk, I walked up to a player, smashed the right bumper, and the camera zoomed in when suddenly it went to an external view and I saw myself being assassinated.
A half second later I got a showstopper medal and an assassination medal with my shields gone and I was like DA HELL?!
Yeah, good times, huh? I was playing grifball and got my own showstopper once. Explain that, huh?
When I checked gamer profiles I found the guy was from Colombia and the rest of the team were all from outside the US, too.