Nearly all the cars that have two different main oil grades listed like my own Volvo TDI only have only one oil recommended by the Iffy lubes and dealers. You can ask for a different oil, but they always recommend the one in their program first. My car for example can use 30 or 40 grades, but the local places don't mention the 30's only 0/40, 10/40 or 5/40.
They will use a 20 grade if that is the only oil listed, as it is for some hybrids, but oddly enough the Ford list has both 20 and 30's for their non hybrids. I looked at two LM places last month and neither has their 5/20 in stock, so it has to be ordered in advance although you can bring your own oil to some of them.
I stopped using Pit Stop because they wanted to charge me the same for using my own Castrol oil as if they supplied the oil and I'm even getting flack from my last place, so I now use a Porsch specialist when he is not too busy.
I missed the fact Synboob (New official term?) is also selling expensive filters and I think it is the most expensive oil I have seen for some time, in fact it's nearly as much as Aral full synthetic 5/40 if you make a serious mistake of buying it from one of their gas stations at 20 Euros for 1 ltr, as it is half that price on Fleabay even with postage.