I have not seen many of these cars being towed. Now there have been a few, but really not many. Autos seem to need a trailer so I would guess the couple I have seen were manuals. Go to the good sam sites and ask there in the dingy towing section. There was a recent post looking for a small trailer for one of these.
We tow a Hyundai Elantra weighs about 2700lbs and has a good stance and length for towing I would guess about 1 and 1/2 times bigger than a smart car (length wise) and have had no issues. Most towed I have seen seem to be either bigger or about the same size as ours. Wife like the room it has to offer.