I think it is perfect over the GM Borla. I work at a GM dealer and I have heard numerous Borla kits on these trucks. I am completely satisfied with my Volant over Borla! The Volant only comes single out is factory location. I have not heard a 14" Magnaflow first hand on a Silverado or Sierra, But I had it on my 2012 Ram Hemi and I liked it a lot. But I think the Volant sounds much better. More performance sound and more unique sounding too! I will say that this is the best sounding kit I have heard! I have had AT3030XL, Banks Monster Exhaust, Flowmaster (super 40&44), and Magnaflow...Sounds just like a Corsa system (same exact thing except a slightly lower grade of stainless)