I strongly suspect that the Rampage's PK18 should handle enough more oil than the Sahara's N'Control coverstock to show a slight preference for it.
Some thoughts on the matter in general:
However, whether the Rampage can handle medium oiled synthetic is problematic, without well above average revs and a strong drilling. That is, on today's TRUE medium oil and synthetic lanes, like Brunswick's AnvilLane surface , 95% of people will need a solid resin, a particle pearl or a polished particle. True medium is a lot more oil, in general, that people think.
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Bowling: Just like hand grenades and horse shoes, you only have to get close.
Life: Deal with what is.