Surprising.
Not the most recent, but a few games ago had a U (rolled White)/Geth/G game where I had some misgivings in the lobby -- all three other players had quite low N7 (like, <200) and similarly low CP and pretty low-level stuff -- one of them was using a Mantis, another had a non-maxed Katana, neither of them using consumables of any kind and low-tier gear. Third was had a low-level Revenant. However, when it came to the actual game -- plenty of teamwork, much attention paid to objectives. People went down at times, but lots of revives, people were willing to gel... think maybe there was one bleed-out in the game. Successful extraction.
Contrasted with an earlier game (Jade/U/G) with slightly more experienced and with slightly higher-tier but badly chosen equipment (the host being a Cabal with a Raptor, Tempest, and Pistol Amp gave me pause, since WTF), but where the host completely ignored objectives (didn't even try to get near the W3 hack but even with his obvious score-whoring wasn't exactly topping the board, either), nobody other than I was willing to gel, terrible play overall. Ended w/ a mid-game wipe since I decided it wasn't worth trying to carry them any more if they were going to be both selfish and incompetent.
Games like the former are why I'll often risk readying up, but games like the latter as well as games where the host proves willing to disconnect on being taken down make me hesitate.