For what it's worth, about 2 or 3 years ago I did an informal test of Surfix Outdoor oil and other oils on test pieces of Cedar strips, mounted both horizontally and vertically. All the oils failed to really survive UV/Sun exp., but since they're not that loaded with UV protection, if at all, the results weren't exactly surprising to me and others. Left the test strips out for a year.
Surfix is easy to apply, dries quickly, and if used outdoors, you would need to expect to reapply the oil often depending on your level of sun exp.
I used General Finishes Outdoor Oil, Linseed Oil[boiled] Tung Oil, Polymerized Tung Oil, Surfix to try them out.
I've also tried some of the above on Mahogany, and Purpleheart as well. Even the GF Outdoor oil which has some Resin mixed in didn't match the UV protection of my Sikkens Cetol finishes or my Epifanes Varnishes. So, be prepared for some gray fading if you're just apply the oil. The Wood Lignin breakdown from UV rays is a tough one to beat.... [sad]
There ARE other oils out there, so this is in no way a total test or last word type of thing on them as an Outdoor Finish... [smile]