02 Sensors, Question - Front/Rear SAME??

Are the 02 sensors for the front the same as the rear? I thought they were different, and that they specifically had ones for upstream and downstream. But I PM'ed a guy about a classifieds ad since he was selling two 02's but didnt specify front or rear. He got back to me saying: "The part numbers are the same for both front and rear as long as it's a 96-04 stang."

Is this true? I also thought the fronts had heaters, as compared to the rear.

Also is Bosch a good brand? I need a new front 02 sensor and cant find any online, anyone have a link to a good quality brand?

Thanks!