It's hit and miss. Last night was the first night ever where two friends and I were able to load into two games with no issues whatsoever. In game, there was still your typical lag spikes here and there, but that isn't to be unexpected.
A few nights ago, though, was the worst night all year - tried four a solid hour and had no luck. It was always one of a few things - one player didn't make it to the lineup screen, or everyone make it to the lineup screen and the host cannot move their cursor, or the opponent team quits out at some point in the process.
Great game mode, but needs some work on the matchmaking for sure.