So, I stopped in my local AZ to pick up stuff that I needed to and have a look'round. What I found in their discounted oil section was some 10W30 Quaker State Ultimate Durability Full Synthetic(QSUD) for $1/qt. So, I bought the last few available. Every other oil was 20W50 and I have no use for it! Ringing up at the checkout, I was telling the guy that I just want some cheap oils..."I don't care if it dino or syn"! He says..."You know, you can't mix the two"? Well, do I really need to tell the rest of the story? You can imagine where I went with that conversation! He mentioned that this information about mixing comes from their training. Although, I don't just look for oils to mix for the fun of mixing but, I do mix straggle qts of oils and, drain my qts/jugs of clean/new oils into a larger jug after doing an OCI. Any comments or questions about the rest of the conversation?