Outside of XDP and Vulcan, what are the prices of some of the ISSPRO EV Series Gauges, and Auto Meter Z-Series? I have a gift cert. to xdp but I want to buy from vulcan. I am looking to arm myself with some knowledge before I start talking to them. There is a 40$ difference in price between the two. I don't really care which is better, I just want the complete kit with the fuel press. Any ideas, guys?