There have been multiple thread where the issue of Volt MPG in CS mode comes us an questions of real-world tradeoff vs say a prius in medium length trips (say 100-150 miles) of a mostly highway trip. I just did a 130mile trip this week and figured I'd share my data. We can deal with EPA numbers, with is 35 EV + 40highway so EPA for a 130 mile round trip one would expect 2.375 gallons and 54.7 MPG. A PiP with 50mpg highway and 11 EV miles would use 2.380 gallons. A EPA prius would be getting 48mpg and use 2.708 gallons. Then people here pos their real-world PiP data which is much better so .. yada yada yada.. Real world for a reasonable Volt driver is also better than EPA. My EV mode data is 17% better, over 6000 miles, than EPA. My lifetime CS mileage is above it but not by as much, in part because more than half my ICE mileage was driving the car home when I purchased it. Below are my screen shots from this weeks trip to airport and then when i got home. I was mostly going with the right lane flow, though I passed a few times. Most driving was at 65mph with a few sections (maybe 10 miles) at 70-75 and maybe 10 miles (all EV) at < 45. Temps were upper 60's going, about 80F on the return. THere was no hypermileing (I had passengers), though of course I maintain a good distance, accelerating and decelerating smoothly. I just went with cruse control as I find it produces better EV range and better MPG. On the way there I used Mountain-mode to save some EV for the slow sections right around the airport, so I still had 15 miles of EV showing when I stopped. To airport was 35.2 EV miles and 63.2MPG The screen after the overall round trip. Round trip it was 48.9miles EV and 46.8 MPG. The fuel used was 12.9kwH + 1.72Gallons for overall 76MPG and 61.8 MPGe. Not too shabby for a 130 mile trip. I think there is more to the EPA variance with the Volt. Every time you accelerate enough the car may think you want to pass and drop from 2-motor mode to 1 motor. I just went with cruse control, and get better MPG. I think the EPA cycles, which don't have a any real segments of constant speed, make it hard for the car to know when to use two motor mode and when to use 1. It thus makes it hard for the battery buffer to really show its advantage when doing highway driving. I expect the PiP has the similar issues which is why we are seeing many people getting HV numbers well above EPA. Testing PHEVs just has a lot more variations and even more so than for an ICE, YMMV. So to those that say the Volt's gas milage is poor, I'll just reply that it must be the operators (including those at the EPA), like the people that only get 40mpg from a Prius. My most common runs that need gas is the airport, and in my Volt I'm getting 45+EV and 45+ MPG.