Without Advanced HID support, what are the limitations when using Traktor?

I keep reading that Traktor doesn't have "advanced HID support" but what does that mean exactly? What issues/limitations am I likely to run into?

I've read potential lag issues, making scratching difficult (which I don't do anyway), also no waveform display on CDJ. Some people don't seem to have a problem with traktor in HID mode.

Thanks!!