It is easy enough to do the math and come to the conclusion that C8 MCT oil will raise your blood ketones for less on a cost per 1mm rise versus ketones, but there is so much more that is going on behind the scenes.
Here is a video interview of the late Dr. Richard Veech* explaining why C8 won't end up working in the long term in the same way as ketone ester (and we aren't even discussing the GI issues with C8)
Frank LLosa
* Dr. Veech was Frank's wife's Godfather and his inspiration to get into ketones.