I bought a cheap proline cordless grinder and have only used it tice i think and both times was to clean my bucket trowel after forgetting to clean it..
I think they would be handy for site work but if on domestic and using it a lot then power corded will be better then no worries about losing battery power....
IMO though a table saw will give a neater/straighter cut all day long and less stress on the wrists........
