TF2 Client Upstream Question

Evening gentlemen,

I'm having some friends over soon to play some TF2. However, I have terrible Canadian intertubes, with a shamefully low ~1Mbps upstream bandwidth. Do you, oh TF2 hivemind, think that'll be enough for three clients behind one router to co-exist and play comfortably, or should we abandon the idea altogether? I can't seem to find any information on the average upstream required by the client...

Thanks!