I too prefer synthetic. I was just browsing Honda parts warehouse and noticed the Oil was made by ExxonMobil. I know many people on here swear by Mobil1 or Pennzoil, just wondering if anyone has analyzed it themselves. I know I could send it off myself, but this would take two oil changes to come to a conclusion.
I sent off my Mobil 1 Synthetic to Blackstone Labs. IIRC, at the time, my vehicle had about 45K.
For best analysis, I didn't send the first batch of oil right after I went to the Mobil 1 Synthetic but waited till the second change so it was more likely the old oil was out of the system. So it went 1) change from dino (or whatever the person was using before I purchased the car) to Mobile 1 synthetic, 2) perform another oil change at 3k, 3) send the third change's oil to the Labs after 6k.
Results were excellent. The elements levels were all low / highly acceptable. There was still a high quantity of the additive Mobil 1 uses (i.e. it hadn't broken down/been used up).
Blackstone Labs said I should try putting a couple thousand more miles on the next batch of oil and send them the results again to see how the oil performed at something like 8k.
I planned to do that, but then I decided to try the Mobil 1 Synthetic 0W-20 Advanced Fuel Economy. Of course I had to wait and do two oil changes, so on my next oil change I'll be sending the oil off to Blackstone Labs.
Eventually I will try a longer 8k run on the oil and send those results in too.
If you don't want to send the results in yourself, check out
More specifically, check the Oil Reports portion of their forum: