In terms of quality, I can't tell any difference between Griswold and Wagner. In fact, after Griswold went out of business, Wagner bought the molds and continued to use their processes for years afterward. But collectors value Griswold more highly, so as a long-term investment, those are the pans you may want to keep.
However, my favorite cast iron pot is a #8 Wagner round dutch
oven -- light, thin walls, the lid fits perfectly, and it's the perfect size for most meals. I had a #8 Griswold dutch oven and I didn't like it as well, so I sold it. So in the end, I'd suggest that you hang onto the pans that you like best. In the end, it's all about how they perform in the kitchen.
"The rule of no realm is mine. But all worthy things that are in peril as the world now stands, these are my care. And for my part, I shall not wholly fail in my task if anything that passes through this night can still grow fairer or bear fruit and flower again in days to come. For I too am a steward. Did you not know?" Gandolf