I would like to ask the advice of you good people who have some experience of the above.I need to grind down welds in some inaccessible places and am looking to buy a die grinding bit which I hope to fit to my router (which unbolts from its springy frame/fence device).I would like to ask what are the better makes and materials I should be looking for,is Tungsten Carbide good enough.I do not want the expensive top of the range nor the cheap copy that lasts 2 minutes.