The VRS and UPR are one in the same as VRS makes them. I have the VRS X in a box still waiting to go on. Quality is TOP notch, they use Magnaflow cats if you get a catted one and they have the best ground clearance of all the standard length mid pipes for our cars.
If the UPR setup is not in stock, just call VRS and order whatever you need. Also is a perfect time to have them put in a bung for a wideband as well. They charged me another $20 for the wideband O2 bung, just make sure to tell them to put it in the driver's side.
Or... if you get the UPR, their 5% discount code during checkout is SHAZAM. It is a public code so I'm not breaking any sponsor rules on anyone's site giving it out.
2000 Mustang GT Steeda #0048
Just because I give you advice, doesn't mean I know more than you. Its just means I've done more stupid ****.