Thanks for coming back on this. I got this mixed up with another LM additive. So thanks for correcting me.
As per your comment about not putting synthetic oil in an engine used to mineral oil previously; in theory you are right, however, if you know LM products well enough, you might have come across LM Ceratec. It will bond with the insides of the engine like glue, and avoid any leaks, and even reduce rattle noises. So if someone is afraid of such reasons, there are good solutions.
Having said that, the memtioned Corolla has had 84,000kms which is nothing in terms of engine life. Unless the engine has been kept in pretty bad shape with little or no maintainance, I will be fairly confident to change to synthetic oil. On the contrary, if the engine had no known history, or had been driven for 250,000 kms or so, I would think twice.
JustSayin
Sent from my HTC One using Tapatalk