The big problem with oil recommendations is that basically when people say that they have had great results with any particular oil what they are actually saying is that their engine hasn't catastrophically self destructed in a way that was clearly due to their choice of bad oil.
On the other hand, they might have bought a batch of identical engines, run them all in on their dynamometer, stripped, measured, examined and documented the internals, put them back together then run identical extended duration stress tests on various oils before repeating all the measuring and examination. After a few rounds they might well find a pattern to which oils do what to the engines. The rest of us will keep going by the grade that is suggested by the engine manufacturer, the various approvals that the oil appears to have and the various marketing claims...
I've been using Motul 7100 4T 20W-50 because it comes from an apparently reputable manufacturer, is suggested as being appropriate for air cooled bike engines, I can get it for what strikes me as a reasonable price (incidentally, the S & S recommended Mobil 1 was blindingly expensive in the UK last time I looked) and given that the X-Wedge gets 6 litres of the stuff and has a short oil change interval then the chances of it being in the engine long enough to deteriorate far enough to worry about are low.
There are places that will do a basic analysis of oil for not a huge amount of money per test but you'll need to go through several oil changes to get a feel for what is normal before changing anything anyway, and remember to get each batch of fresh oil tested before it goes into the engine.
So in summary, get some 20W-50 that is sold (at an acceptable price) as appropriate for big air-cooled V-twins, semi or fully synthetic, change it, and the filter as often as you should and the chances of having any oil related problems are distinctly low.
Back when I was mechanicing at the bike racing I had some good discussions with some people who worked for lubricant companies: at the time most, if not all of these companies bought in their carrier fluid which would meet a specification but wasn't necessarily identical one month to the next depending on what was available from the refinery then they blended in an additive pack which was also bought in, checked that the blend was within specification, bunged it into drums and sold the stuff. Several of the companies were all using the exact same additive packs and pretty much the same carrier fluid for their own brand oils. Telling the oils apart is difficult apart from the colouring that might be part of the mix; the Motul stuff is a rich red colour!
