I have two Penzey's boxes with plastic bags of spices in them, filed alphabetically. Plus some jars in the cupboard.
Some things that we use regularly: Greek and Italian salad dressing mixes. I also use them for marinades or rubs. 4S (either Smokey or not) on all sorts of things. Epazote is a must in our family for bean-based dishes.
I have bought seasonings from Ocean State Job Lot (.89 here and they're not very good) but sometimes you just need to not spend a lot of money.
I've also bought spices from Costco for the same budgetary needs but they do have a better quality than OSJL. But they're still not up to Penzey's quality.
Like another poster said, if I'm making something special or want people to really love it, I'll make sure I use Penzey's spices.
NHWX