I have not used those particular arms but have used Loc Line and Ultra Light arms, which are both the same thing.
Personally I prefer the Ultra Light over the Loc Line style, though people will differ. I found UL easier to position and hold position for my needs, though you may need to loosen the clamps (often I do not need to.) The ULs are usually slightly heavier and may not have quite the flexibility to position as precise as the Loc Line, but never a huge drawback for me. The Loc Lines are lighter, you can add/change sizes by adding the rings. But sometimes the Loc Lines make noise when moving them which in theory can scare fish. (I have not had that issue, but some people mention it so I threw that out there.)
One of the main issues I had with the Loc Lines is when the connections pop off they were a bit of a pain for me to deal with, the screws and mounts of the UL are easier for me to deal with. It does look like the Loc Line style you are looking at may be easier to deal with, but looking at the Flex Arm, for example, it often drove me nuts attaching the arm back to the base in my system. Probbably more me than the system itself since so many people use them 
