Installed a V3 from Josh about a month ago. Install went smoothly except for the v-band. The bolt could be a bit longer, but not a big deal. Use a bit of wire like a tourniquet to get it to come together. Fittiment is good, welds look nice, the tip and the GMS stamping were not laid out really well, off center so I eased the issue with a PortaBand and grinder, and get some other bolts as has been stated before. The sound is very similar to a Cobb. I am running catless. Gutted up and Perrin DP. Not loud in comparison to JDM-type cans, but not as quiet as stock. Low deep grumble at idle, I almost cannot hear it at 3k, but I definitely can hear it above 4.5. I decided not to go with the powder coating from IIR and will be using flat silver BBQ paint from the weld on the tip all the way through to DP. All of the little issues I would have been very upset with from Cobb, but for $2XX to my door its almost cheaper than just buying the 3" SS pipe to make my own. If the muffler gets way louder or the hangers rust I can just buy the Borla muffler and resonator and have my GMS/Hush.
All in all, great value oriented exhaust. The sound is nice, no drone in sedan at 3k, might have some rust issues in the future so make sure you go with IIR powdercoating or Hi-Temp paint before weather, and the exhaust is nice looking.
And get 15mm long hangers.
Thanks again Josh