I had a conversation with the people from Peel Away recently on this subject. They say that the important thing is knowing what kind of paint was used for the paint coat that is right on the brick. If this was an oil based paint, they say that Peel Away 1 will do the job. If it was a latex paint, you must use Peel Away 7. If you don't know, they suggest that you test a small spot with Peel Away 1. If the test works OK, go ahead and do the whole thing. If Peel Away 1, does not work, you have to use Peel Away 7 which is much more expensive.
I know that you will get good results with their products but I still question if you will get all the paint and stripper out of all the little holes and cracks and crevises in the brick. I'm sure that the roughness of the brick face has a lot to do with this too. A relatively smooth brick should be pretty easy to strip well. I have not used it so I am not speaking from real experience but I do know that their products are pretty darned good for some jobs. Be sure that you follow the instructions on use and safety to the letter.