Flux core wire?

I used one years ago that my neighbor had and he was having all kinds of issues with it. Most of it was wire related and his lack of skill. We changed the wire, I helped him dial it in with the limited controls he had and it served him just fine. Biggest issue, the wire was always hot, the trigger only controlled the drive wheels. Hopefully the rectified that issue, this was over 15 years ago.
Kevin