Is it Opie Oils?
I'm going back to Ester synthetic but torn between Silkolene Pro S and Nano Drive.   Opie have a promotion on for the Silkolene (1 free litre per 5l tub) but no deals on Nano.   I like to bulk buy as I do my oil every 3-5K, which makes Nano expensive!  Anyone know of a place that will sell in bulk for a decent discount?
Cheers!
P.S. Another reason I'm torn is because of this - 
https://www.tegiwaimports.com/blog/445/     They rate the Silkolene very highly but there's a clear benefit in going to Nano.   Do the particles in it block anything like filters and oil ways?  Some additives are known to.