I have a really effective test I use before I buy a pack of dsp. I ask myself "Do I have this already?" If the answer is no I feel compelled to buy it. If the answer is yes, then I ask, do I need a second pack, so I can use one and hoard the second?
My dsp is pretty scary right now, I could probably wall paper our house with it, I don't know why I can not resist new paper packs? I really should be more selective before buying it!