There are companies out on the Web that will do a chemical analysis of your oil for about $20.00. Usual turn around is 10 days for a full written chemical analysis. If you are interested in that let me know and I'll find out the name of the company.
The trick with the paper towel is used by a friend of mine that also uses a trick with newspaper on setting bearing clearances. While I lean more towards measuring with a micrometer It's hard to argue with NHRA national records that he has.
I have an article that was in R&T a long time ago concerning testing various oils on the market at the time. I think 14 or 15 diffrent brands were tested, but what I do remember was at that time it was Mobil1 far and away better than the dino based oils.
Next closest was Amoils (?) which was/is synthetic.
I personally use Mobil1 in both my cars, and have had great expirence with it. One caveat being if you've got a leak or burns oil don't bother, It can get expensive.
71 250 Coupe
92 400E Sedan
90 944/S2 Cabriolet