I' trying to decide if I should do wing chun a ninjitsu. It seems very difficult to find information on ninjitsu so I just found these videos, and I would like to know if they accurately describe the art.

Also, more importantly, what do you think are the advantages/disadvatages of both arts on the street?

Negative. Best thing to do is to go to a class and watch them.

Agree with Crablord and Leo, those two arts will take quite a time to become proficent in. If you have the time, then go check out both classes, ask the instructors lots of questions, try a class or two of each, then make your choice.

Best defence for the "street" is awareness, common sense and some strong legs to take you away from any danger.
"Let your food be your medicine, and your medicine be your food" Hippocrates.