I currently have the 8289ws and pull with my 2014 GMC Sierra 5.3. I did add airbags for a more level ride but only have to inflate to 20 psi when connected. No problems towing but mileage is only about 8 mpg.
Same here, towing an 8265ws with a 1500 5.3 with air bags. No major concerns, a little slow on the hills and the only thing I need to do is upgrade to an LT tire.