Exogenous ketones can help you get deeper into ketosis, and faster, but for most people it will be unnecessary. If you fast a day, by the end of the day you'll be using ketones. If you switch to a very low carb high fat diet without reduced calories, you'll be in ketosis within a couple of days. Faster if you exercise.

I can see exogenous ketones for health reasons. Perhaps for those using it to treat epilepsy or maybe Alzheimer's. High level of ketones are not associated with greater weight loss though. Some believe it is ketones that diminishes appetite and helps with weight loss, but others think it may be the lowered carbs. KWIM?

I think you are probably right in that for most people MCT, salt, and magnesium would have a similar, if not the same, effect. I have not researched the product though.

I think the question what is your reason for seeking deeper ketosis?
For therapeutic benefits? Then yes, this would help but so would coconut or MCT oil at a hugely cheaper price.
For weight loss benefits? Forget it. It doesn't work that way. You must burn your bodyfat for weight loss. Ketones are a product of fat oxidation. They do not burn your bodyfat. They are the product of burned fat. If you provide and outside source, your body doesn't need to make its own ketones.

Seconding above ^^^^!! Waste of money if you are not on a Keto diet for neurological reasons.