The metal frame pliers you choose will depend on a couple of factors:
1. The combined thickness of the studs and track to be fixed
Thicker track and studs will require pliers with a larger capacity.
2. The working space available to use the pliers
The location of the jaws will determine the position of the pliers when in the punching position. Pliers that have jaws positioned on the underside of the body will be at 90 degrees to the sections being fixed when in the punching position.
Pliers with jaws on the end (or nose) can be used in restricted spaces.