I actually emailed SoA about the towing, and they told me the following about the sedans--their hitch receiver won't clear the bumper (cover) on the Sedans, but they do on the wagons since the bumper design is slightly different.
etrailer.com lists a hitch that will fit the Sedan body style, and they suggest a longer receiver to extend the ball out and away from the car.
When I emailed them, they mentioned that you *may* have to trim the underside of the bumper cover to get everything to mount, but you shouldn't notice it (unless you routinely roll your car or go to shows and put mirrors under it
Originally posted by rsholland
Speaking of towing with the WRX and STi in the '04 US-Impreza brochure, their wording seems inconsistent and confusing. For example:
• On the specs page, they do list 2000 pounds as the limit for both the WRX and STi, as Ghostrider mentioned. However...
• If you look at the accessory tow hitch picture, elsewhere in the brochure, it mentions (2000 pounds) for the WRX wagon, and there's no mention of the WRX sedan or STi. This suggests to me you can tow with the WRX wagon, but not the WRX or STi sedan. You can certainly use the hitch receiver for a bike rack attachment.
• Also, you should be aware—that for any US-spec Subaru—you can't tow over 1000 pounds unless your trailer has trailer brakes. This info is somewhat obscure in the brochures, but it is definitely mentioned in the owners manual.