The thing is, this oil has been rendered totally obsolete by the crop of ultra high VI OEM 0W-20.
The RP spec's are HTHSV 2.5cP and 140 VI.
This oil is not much lighter than a typical 5W-20 dino if not heavier in service after the dino has sheared some.
For example the Sustina 0W-20 (HTHSV 2.6cP, 229 VI) will be dramatically lighter on start-up, still lighter at normal operating temp's with the added benefit of a higher HTHSV.
In fact the usefulness of all the so-called light 5,10 and 15wt race oils has been severely challenged by these new high VI 0W-20 oils. And when the up-coming 0W-16 grade becomes available even the viability of the lightest 2wt race oils will questioned.