marsal is not that popular here in the NYC area compared to bakers pride. i have had some good pizza out of both ovens (not made by myself.........) Maybe you could find someone that will let you bake with one.
from what i have read Marsal is cheaper.
Marsal has 0" clearance, not sure if this ACTUALLY means they are better insulated but one would assume yes.
Not sure about their baking surface vs the bakers pride Cordierite. It is thicker, but not sure about the thermal properties.
the marsal burner design (which goes from side to side instead of front to back) makes sense - I would think it makes for a more even bake.
I had thought about opening a place and would probably give the Marsal a try.
one last thing i dont know is whether Bakers Pride uses 100% stainless (vs aluminized steel used in much of the Marsal oven).
good luck and have fun.