You can't ever really drop a module. PTC will remember everything you ever bought and bill you for it ad infinitum. You can wrestle with them each and every year over how much you are willing to pay for maintenance. I did that for years, now all software issues have been outsourced to another group who knows nothing of our license history so they just blindly pay double what I used to negotiate.
PTC quality philosophy: We've upped our quality standards. Up yours.