If you aren't aware of the different tolerances in Tandy letter stamps then your work will look as crappy as the poor tolerances.
I started stamping the "T " to be followed by an "I " and you can really see the difference where the "I " stamped higher than the T.
I turned the stamp around and it lined up much better with the T and you can see how much lower the second "I " is from the first.
So if you aren't getting good results it could very well be the crappy tools being supplied by our suppliers and NOT you.
I have 3 different brands of stamps IVAN , Craftool new and VINTAGE...they where all the same around the edges...but the Ivan set cuts much better.
On all of them I took a flat file to the edges so they would all line up straight instead of a little mold edge sticking out...now all is good! But IVAN is a much better Letter/Number stamp for the same money. Not so much filing. Plus my vintage stamps are slightly wider than the new ones, so if I accidentally mix the letters when using a lot of them a trained eye would catch it in a second...it may be a millimeter in width of the mold but it is enough to even through me off sometimes the letters may get mixed up between boxes I do have 2 kids that play with them as well sometimes so it happens from time to time:). I have to look for the corrosion on the old ones so I know I am not using them to stamp along side the new ones.