Your paying for the name brand there thats it. like sevtchevelle said You dont need 7 hammers. I use 2 hammers and thats IT.
all i have used are flat slapper and heavy spoon , shrinker hammer that has a shretcher face on the other side, retangle dolly with a slit dip on one side and a crown on the flip side, hammer with a pick to. oh a dolly that fits in conturves to(its that standard one you see outh there at autoone.)
these can be purchased for much less than 300+
what i used most on my on my 32 chevy was the slapper, both dollys, stretcher shrinker, and a small propane torch and water sprayer (for expanding metal and quickly cooling it so it shrinks molecules more that it expands then)
before you buy a set visit metalmeet.com and learn about the tools and what specific situation they are need for. then you can eliminate the tools from those sets that you don't really need