I had always used Solo in the past, but this year as a small experiment I purchased one Jacto, one Field King, and one Stihl backpack. The only one I have personally used has been the Stihl. I have thought about testing the others, but so far I really like the Stihl. I messed up when ordering the Jacto and got one make with a dark blue plastic, which is going to make it harder to see how much chemical it has in it. There was also some assembly required with the Jacto. No comments yet on the Field King, but I will try to update this once I have used them all.