The 6.4L does not take any special oil filter and you have a choice from cheap to expensive. The recommended Mopar oil filter is somewhere in between cheap and expensive. Some people like to use the Mopar SRT filter that is fairly expensive but not proven any better than say a M1, Napa Gold, Wix, etc. FCA recommends PUP 0W40 but does not require it. What is required is a 0W40 synthetic oil meeting the spec in the owner’s manual. M1 0W40 is not certified for the required spec and that is probably because M1 said FU to FCA in 2011 or 2012. No question M1 0W40 would pass the spec if they wanted the certification. M1 0W40 use to be the recommended oil for the 6.1L & 6.4L before whatever happened between FCA and M1 happened. FCA probably does like the high moly content in PUP 0W40 for the 6.4L for it makes the cam phases operate smoothly – not to say other 0W40 oils would not have the same results. Interestingly, all the cleanliness and etc touted by Pennzoil, if you read the fine print, does not apply to the PUP 0W40.
Bottom line, with a 7qt sump an oil change will run a bit more than in many other vehicles but using a moderate priced 0W40 meeting the FCA spec and a good, but reasonable priced, filter will not break the bank. However, being older myself, I can certainly relate to getting under a low setting car. If I had the ceiling room I would have a lift but I do not so I do not.