The only problem with silicone couplers is they can and will blow apart. I dont care if your have a welded bead on the end of the pipe, t bolt clamps, whatever. They can and will come apart at the worst moment. On all of our build we use v bands and leave only 1 silicone coupler in the system (in case it over pressurizes ) and leave that coulpler in an easy to access spot. If you can weld it all up in steal I would rather see you do that. How much boost are you planning on running? We seem to have had most of our problems when we run over 18 - 20 lbs.