G Thomas and Tubal Cain both recommend Shell Ensis oil for general rust prevention in the medium to long term. Reading between the lines of the only ad that I have been able to find, the stuff now named Ensis does not seem to be a straightforward oil. However good it may be, it does not therefore carry the endorsement of the Gurus. It it is only available in large quantities and may not be suitable for repacking by, for instance, ME clubs.
What are other people doing and what success are they having?