i read that the stock prius I tries are garbage, so once they are worn out does anyone have any recommendations for tires that have very low road noise? I don't mind sacrafacing a few mpg for comfort and grip as well as long I can pump them to mid 40's psi

 

Tires the size that the Prius runs easily will be able to be max pressed to 45psi or better in most instances.

I would go for major name brand tires from Michelin or Goodyear. Other brands should be fine also, but the above 2 manufacturers are known for having the best tread compounds and technology. Although Nokian has a wonderful true all weather tire that includes a severs service rating, which means it qualifies as a traction tire during the winter and you can avoid having to get out and chain up. But they easily cost over 100 a wheel.