I have used it twice. Yesterday I did some line sculpting with a 7rl and today some powerlining with an 8rs. I seem to prefer running my machines at higher volts because I ran it at 8 volts both days and it lined perfectly. I run my Neuma Hybrids at 15v which is more than what most people seem to prefer. But it works for me since I have a pretty fast hand speed. I do a second session on the piece I powerlined today in 3 weeks so I will keep you posted on the healing.