Engine oil IDEMITSU or Pentosin

I think Idemitsu is the better option if you have access to it. Mostly because it was developed for the rotary engine.

Idemitsu to both, because it’s designed and tested on rotaries.

Pentosin is fine, Mobil 1 is fine, Castrol, whatever. I put Mobil 1 in my racecar but castrol in my daily because it burns oil and I want a heavier weight that I can't find Mobil 1 in. Pentosin or LiquiMoly are good, but don't put too much thought into it.

I use idemitsu rotary 20w50

I stick to Idemitsu. I have a Sohn adapter fitted, so it's 10-30 Idemitsu in the engine, twice a year and Idemitsu Premix in the Sohn adapter and in the fuel tank.

I use pentosin. Made for vws. Change it every 10k. Good quality filter and you'll be good

I don’t use the Mazda-branded version, but Idemitsu is my go-to oil in all of our Mazdas

I use Pentosin in the e46, which I believe is BMW OEM supplier.

Idemitsu is the only premix and engine oil I’ll use ... you can order it for a good price from TREx performance out of NJ and he will ship

The oil was Idemitsu Synthetic 0W-20 with 12.5k miles on it. Once again, trace metals and flashpoint were within normal range. I also ordered a TBN to measure the amount of additive left and that showed there was still plenty of active additive remaining.