Having a family, we have been way past due for something new, and purchased a brand new 5sp manual 2.5X almost a year ago.
Wanting a 5sp, something with adequate space for 4 adults and a carseat, got decent mpg on regular unleaded, and was in the low $20K range out the door, was a tall order that only the Suby met.
I had seen past reports of most people seeing low 20's mpg, but the insurance company liked it(dropped $30 a month even with keeping all our existing cars on the policy), and the awd/traction control/abs has been great for our wet and sometimes snowy climate.
Our first 1000 miles was only returning ~22-23mpg, in a motor that was fairly noisy and then started to get a rattle when hot. At ~1500 miles and after a couple complaints about the noise Subaru decided to replace the engine. Not sure if they missed a bore size or what happened as it sounded like piston slap to me, but Subaru sent a pair of tech's and a new motor OVERNIGHT from Japan and had us all fixed up in about 3 days. I saw our Suby in the shop with the engine out and the other getting prepped so I know it wasn't bs.
After that, mileage was much better, up to around 26mpg in mixed driving. The first service came, 3500 on new engine, 5000 on car, and it bumped up to 27.3 mpg where it has stayed in my mixed driving commute.
Recently we took the family on a trip over the pass, climbing from Sea-level to ~5200' and back. I drove it pretty hard, floored at the top for a couple miles, never lolly gagged under the speed limit, and passed alot of slow pokes. No coasting, no drafting, P&G, or any tricks like that. Mpg for that trip came to a surprising
29.7mpg average.
This is par with our A/T Civic DX so I am pretty impressed, being the Suby has awd, is more of a brick, and has to lug around another 800#'s compared to the Civic. Large swaybars keep it's handling sharp, it's enjoyable to drive and doesn't start to get sloppy until around 80mph on the mountain twisties.
The motor makes good torque thru 3500-4000 rpm and doesn't need to be revved. I typically get on it pretty hard up to around 3500rpm and then shift up to keep the RPM under 2000 when cruising. For whatever reason, it doesn't seem to affect mileage if you accelerate easy or not, so I wouldn't say I wail on it but I do put my foot in it often.
The automatic version gives up a fair amount of power compared to the manual, and turns a spirited SUV into one with "just adequate" power for the daily grind. I did notice in the city, that the automatic version(our loaner) returned better MPG's in the stop and go thanks to the TQ multiplication of the converter, but lower mpg on those open 50mph county roads.
While not a hypermiler by any means, it's a great vehicle for those needing a do-all for the real world. Note that in 2011 Subaru introduced a new DOHC boxer 4 engine, which brought some more HP and better mpg to the table. 2010's still use the SOHC series of the prior years. Just an FYI if I've inspired you to go shop for one, don't get sold a 2010 unless it's offered at a decent discount to the 2011.
Just my .02