The lower support for the downpipe is important. It's job is to locate, and support the weight of, the downpipe; and to help isolate the turbo and manifold from the stresses of flexing/movement of the exhaust system.

The design of this band support/L bracket is similar to the one used on 700 Turbos. It works. And it works better with a flex coupling downstream to truly control the flexing and strain on the system.