@Kilgore Ray said only 20% of vitamin E is absorbed when applied topically. However, he claimed that steroids dissolved in vitamin E have close to 100% absorption when taken orally. This is why he always referred to oral administration when referring to Progest E.
Topical application of steroids dissolved in vitamin E does have the benefit of slow, sustained absorption. However, if you wish to absorb a desired dose of steroids, such as 10mg of testosterone, you will need to apply 5x more solution because only 20% will be absorbed; this would require you to use 5x more steroids and 5x more vitamin E, and funnily enough, using 5x more vitamin E is the main issue here, because vitamin E is an expensive solvent and applying large amounts of vitamin E oil, is very tricky due to it creating oily skin (as it is not readily absorbable, compared to ethanol or DMSO).
Vitamin E "Oil" from NOW. has 510mg of alpha-tocopherol per 1ml, so you can probably dissolve 50-100mg of steroids in there, per ml, with ease. The NOW Vitamin E "Liquid" has 300mg of alpha-tocopherol per 1 ml, so you can probably dissolve 30-60mg of steroids per ml of oil with ease.
The NOW Vitamin E-Oil with "Mixed Tocopherols" has a 58mg amount of alpha-tocopherol per ml; I don't know how much of the other isomers it has, such as gamma-tocopherol, so I wouldn't use that immediately. I am sure NOW customer service will tell you how much total mixed tocopherols is contained within a serving.
The product that you linked me, is 100% tocopherol solution; very good, much better value than NOW products. A way to see the concentration of vitamin E oil, inside a product is to see the IU per ounce. This product has 42,500 IU of d-alpha tocopherol per oz, which means that there is 28,475mg of d-alpha tocopherol per oz (multiply IU by 0.67 to convert to milligrams). So it is pure tocopherol, and it says also so in the ingredients list.