Hey Tony. The x section does not contain any emissions devices so you don't have to worry about that. The dealer can't void your warranty outright, they would have to blame any issues that happen with your car on your mods in an attempt to deny a claim. If a suspension component goes, they can't try and pin it on your x-pipe.
Have you considered supporting a vendor here and have you seen our bolt-in x-pipe with tips
? A cast X-pipe allows for a smooth transition into and out of the X section. The casting of the interior is also smooth, without any protrusions from welds. A proper back purged weld with full penetration will most likely have some material on the backside in the X. Non-cast designs can fail due to stresses and / or possibly lack of proper welding techniques. We've made a very conscious decision to offer the most durable X solution possible with our customers in mind. We've also been using these X-sections with great success on our full line of Boxster / Cayman exhaust systems which are proven to perform, and warrantied to do so on the track for LIFE. We can also customize the tips for you with different colors and logos of your choice. I'd be happy to take care of you if you shoot me a message.
to recently installed a set and had some great feedback.