Just wondering what they are (cost not included)?
Seem to remember talk of deposits of some sort building up from a Porsche mechanic I spoke to who then went on to say it's not worth the extra cost...?
If someone now tells me it is peerless with no downsides (except the thin Mobil One 01W 40) then why don't all manufacturers recommend it and choose semi instead - like Subaru!?

You CANNOT go backwards!! To using semi or natural!

Other than that I think it IS peerless!!

Pete

Advantages:

Those that we are all aware of although some have experienced things which make me suspect it is not always what it's cracked up to be..

Disadvantages:

Two main ones IMHO:

1) Effectively reduces or even eliminates "running/breaking or bedding in" process of new engines often resulting in longer term harmful effects. Engines can have their useful life considerably reduced by the early use of Synthetics simply because it is usually so efficient. If used too early before sufficient miles on non-synthetic lubricant are clocked up, problems include excessive oil burning and bearing problems in later engine life. Rings and other surfaces are particularly prone to fail to properly bed-in and this can lead to all kinds of problems resulting in reduced engine life and excessive oil consumption.


2) Cost must be included here as a disadvantage because it's so VERY expensive, particularly in over-priced UK: circa 33.95 for 4 litres is plain greedy when comparing prices with mainland Europe.

If you really want the full SP on the subject, trawl the web search engine results. There's some interesting lubricant stuff there. I did have a good site as one of my "favourites" and intended to post it here but, it's no longer on my favs list.