The meso sacks are the worst possible way to convert NX into mesos.
Use the MTS for maximum profit (up to 1 million mesos per 100 NX), or even Gachapon if you're impatient or fond of gambling. Both will guarantee you 2-5 times the amount of mesos that you get from buying Nexon's sacks.
The term "wall of text" only applies to ignorants who do not bother to read their opponent's mostly perfectly valid arguments before immaturily attempting to counter them.