How? Killzone 2 features the option to limit matches to those at your own level.
First of all match balancing in team based games doesn't necessarily mean you play with those at your own level. Second, not everybody at the same level has the same skills.
One side is better (naturally). If it's a ranked game (possibly with stat tracking), the players on the loosing side will start to leave the game, which will only make things worse for everyone on both sides.
As far as I can see Killzone 2 will have objective heavy MP which isn't going the make the whole issue easier to handle. Ranking is also way more important than the likes of CoD4, Resistance or MGO.
Lobby system is fine if you are playing with friends against friends, otherwise works terrible with ranking.
How is that more convenient...
Quick get in, quick get out. Match starts with you, ends with you. You don't have to join a game in progress, or leave in the middle of a game.
Why should I play unranked games just because they have a ridiculously system in place. I have never played another MP game that closes lobbies ala Resistance.
Why do you want to play ranked games in a lobby with the same people? Seriously?
Let's say you have average shooter skills, yet you will either keep loosing, or keep winning, in any case there is something wrong which shouldn't be in a ranked game.
Why is it ridiculous? I'm curious, please enlighten us to why the way of Resistance is worse than the likes of CoD4 or MGO?
It's much better for match making, much better for rankings, much better for stats.
In fact, I'm quite shocked that there is someone in this world who thinks otherwise (again for ranked games).
Especially annoying in co-op.
Fortunately we are not talking about coop but that's what the party system is for. I suggest you make some friends if you want to continue playing with same people in coop.