Hey Hive account@takowi,

the ROI is based on hands-on value. Whether the internal price is higher or lower than the external price (exchanges).

Taking the external price isn't possible due to the extreme fluctuations.

With that said: all promotion services take the same data, so regardless of which one you take, the negative downside would be the same. However, with Hive account@smartmarket, you're on the more safer side.

Hope this could answer your question.

All the best,
Hive account@smartsupport