Spend the extra bucks and buy the most expensive one you can find. Porter Cable, Makita, Dewalt, and many more make up the list.
Here is a small story on circular saws:
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?action=productList&N=0&Ntk=i_products&Ntt=Circular%20SawsDo NOT buy a cheap circular saw...
Oh... and build one of these to make the cuts:
http://www.woodwork> I need to make a precise cut of wood to be 24" long and only 4 1/2" wide. >