You can use Nic Salts or Freebase Nicotine E-Liquids with the Aspire PockeX. For RDL vaping, use the 0.6Ω coil with Nic Salts or Freebase Nicotine. For MTL vaping, you can use the 1.2Ω coil with Nic Salts or Freebase Nicotine e-liquids as well. If you've already got Shortfill E-Liquids, the Aspire PockeX may struggle to vaporise the thicker juice efficiently. It's best to use juices with a more even VG/PG ratio, such as 50/50 or 60/40 VG/PG.