They aren't cheap - this one cost around £20 and I have seen them for twice that price - but well worth it. So what do you get? Well the body of the punch feels solid and comfortable to hold. It has an easy to remove chuck and six different sized bits ranging from 1mm to 4mm. The punching action works by pushing downwards on the handle, the barrel turns with a screw motion and makes the hole. It doesn't require a lot of strength to use and is completely silent - no hammering involved!
So far I've used it mainly for making holes for sewing books together and for tag making, but I'm sure it would go through leather or similar if you needed it to. Definitely my favourite bit of kit for quite a while!