You may want to give a try to the modifiers set offered by SP, they come in PBT and POM, so you will get a better idea if it is what you want. Other option could be to ask for examples of caps in PBT thick, and thin to get the actual feeling. There are always fellows that want to help by letting go some caps.
It is good to listen to others experiences, but I am pretty sure you will have an actual opinion until you try the caps yourself.