Currently I have 5W30 M1 , PP , PUP , QSUD (also in 5W20) and Castrol EDGE in the oil stash . My thinking is to run my next fill using QSUD 5W20 for a severe schedule OCI (3,750 miles ) in the Hyundai 2.4L GDI Sonata then have a UOA performed . That will pretty much be the "worst case" UOA using the QSUD 5W20 , so my thinking is : What ever the UOA results that come back with the QSUD 5W20 after my sever schedule 3,750 mile run will surely be a little better in 5W30 with the other synthetic oils I have listed. Therefore , what I ever I get back with the QSUD 5W20 UOA will / should give me an indication of what I can run a 5W30 synthetic I have listed above for in terms of miles ... Your thoughts ?