I have had my 6-speed manual 2013 Beetle TDI for almost a year (I got one of the first three in the country). My mileage has been pretty consistent over that time, since pretty much all I do is drive from home to work and back (21-ish miles each way). Most of that time is on I-95 in the DC area, but I manage to avoid the worst of the stop-and-sometimes-go traffic due to an alternate work schedule. I do get some of it, but not every day. Therefore, I generally drive like a bat out of hell (70mph is about cruising speed on the highway here). Unless I do something abnormal, I generally fill up twice a month. (on paydays-nice how that works out!)
My average mpg for most tanks is 38-39.
My average for the drive TO work is 36-38.
My average for the drive FROM work is 46-48.
Going to and from the grocery store and other stuff just a few miles from home (with a million stop lights), the average usually drops to 30, or maybe a little less.
I travel at different times each day, with generally the same traffic each way. The only thing we (myself, VeeDubTDI, compu85, and others around here) have been able to come up with to explain the 10 mpg difference each way is that 95 slopes ever-so-gently downwards towards the southeast (where I live) as opposed to closer to the city (where I work). I still marvel that the difference is that great.
I know others may not be thrilled with their mileage, but with current prices, I am paying about $1.10 more a tank than I did to fill my previous cars (all gas Saturns, may they rest in pieces) and I get about 150-200 more miles to the same size tank. I’m ok with that.