I have the same Silent Trap you have. They are very nice. Trouble is that I shoot deep holes in the putty fairly quickly because of the short range I shoot at. Even the Longbow drills holes in it pretty quick. My 22 FPE rifle drills holes even quicker. It would help if I used different targets so that I wasn't always shooting at the same spots.
However there is another solution that costs less, and gives you a bigger target area. Also almost silent. Just the sound of the pellet hitting the cardboard box. This suggestion was given to me by Jan Kraner. Fill a plastic garbage bag with old clothes. Loosely is okay. Put the garbage bag inside a cardboard box. Jan said this would stop a .22 Stinger. Clean out the lead pellets without getting messy. No need to repack holes in the putty opened up by your shooting.
The rags are a big advantage over the box filled with old magazines that I originally started with. That was messy, and the box very quickly started bulging keeping the target from laying flat. Not a problem with the rags. When the holes get too big in the box, get a new one. Tape the top closed, and you have 6 sides to mangle before needing a new box. Free boxes of course! Might even be able to raid the wife's closet for old clothes, too!
Have to agree with you. These forums are a great place to get questions answered. Name it, and someone will have an answer for you. Well...most times.