@Laotionne - I think it is safe to assume that the average fire resistant clothing sold at the retail stores is nowhere near the quality of what firemen wear. If it were, most of us would not be able to afford to buy it. The flame resistant clothing the average person buys is not made to withstand the extreme temperatures that a fireman's suit will stand up to.
By the way, the clothing of firemen is also water resistant. I guess this should be obvious, but this is an aspect we sometimes overlook because we automatically think of the roaring flames and not all of the water the firemen come in contact with.