The people that are going to help you have all completed the process and jumped through said hoops without complaint...
Harshness can be due to too high a nic level or a high vg ratio.. It gives what some people call a throat hit and some people require that feeling...
T22 is a mouth to lung kit, i.e you take the vapour into your mouth first and then into your lungs replicating a cigarette...
The v8 stick is direct lung hit.. i.e straight into your lungs.. With this device you can use higher VG (80%) and you will get a smoother vape but dont use over 6mg nic or it will feel haesh...
Try to find a vape shop (commonly known as B&M shpd on here ) which will let you try a variety of devices and juices and see which one suite you best.