All Subies with AWD manual transmissions are towable 4-down, except for the new roadster (and it might be, just don't know for sure) I have an email from the company attesting to that because I contacted them prior to buying my 2012 Impreza.
Here is the email:
Dear Mr. Rafferty:
Thank you for visiting the Subaru Web Site and for your interest in a 2012 Subaru Impreza.
AWD Subaru vehicles with manual transmission can be towed with all four wheels on the ground and the transmission in neutral.
When towing a manual transmission 2012 Impreza behind your motorhome, you would want the transmission in neutral and the key in the 1st position from "OFF." As all new models are equipped with digital odometers, mileage will not accumulate when being towed.
Thanks again for your interest in Subaru products. Have a great weekend, Burns.
John J. Mergen
Subaru of America, Inc.
Customer/Dealer Services Department
Service Request #1-1980576722
Sent: 4/12/2012 04:35:18 PM
Subject: (SR #:1-1980576722) Product Information
Hi - I am interested in the 2012 Impreza. My wife and I own an motorhome and I need to know if the 2012 Impreza (manual transmission) is flat-towable (all 4 wheels on the ground @ 60mph) behind the motorhome and what, if any, restrictions there are. I'm not sure the salesperson really understood the question I asked.