I think these markers are rather charming. I've seen them on a number of Etsy shops but then I got the notion to make them myself. Especially after reading Bunny Hill's tutorial on them.
I ordered this set, along with a jeweler's steel block and a ball peen hammer. The hammer was useless. Too dainty.
It's better to use a small sledge hammer. And you have smash down with conviction. You don't want to be tap tap tapping on it. The letter stamps want to move. Better to just hit it once or twice really hard.
I would also suggest you put something under the spoon to keep it from slipping when you are doing all this smashing. Because it hurts like the devil when you smash your thumb. With conviction.
(okay that's ivy but my herbs bolted and weren't looking very photogenic....)