I have an Hauppauge HD PVR2 "Gaming Edition", which now costs about $135 and I can recommend. The only downside is there's a long "boot time" after you first tell it to record video (don't expect to just hit a hotkey and capture video 2 seconds later; give it more like 10-15.)

For what I'm using it for, latency doesn't matter much. I'd estimate it has about 1.5-2 seconds of latency, but I've never actually measured it.