The cheapest and handiest are the Lee case trimmers. You can buy the set with the cutter, or the plugs by themselves - they will never wear out in normal use. The case-holder can be hand-held, or, as I have done, put in the chuck of one of the many handy little cordless drills that are on sale in every DIY store.

Or, you can buy a Lee Zip-trimmer - you pull the cord like starting an outboard motor - around £20 or so, and you can use it to hold the cases while you are polishing/de-burring them - just cheaper than a spiffy little leccy drill.

BTW, Kleeneeze make the best polishing cloth imagineable - it's called the 'Miracle cloth' and is just like the Birchwood-Casey lead remover cloth except it's twice as big and half the price.

tac