Concerning oil filters, this link, http://www.frankhunt.com/FRANK/corvette/articles/oilfilterstudy/oilfilters.html, is a great resource.
Concerning synthetic oil, what else can be said that gserep1 didn't already say in his excellent overview? There really is no question that synthetic oil performs much better than conventional petroleum oil. Why not spend a few extra bucks and ensure that our high-revving engines have the greatest level of protection possible? And with the extended drain intervals that synthetic oil provides, the additional cost is mostly negated.