Sunlu S2 is what I use.. tips: whatever filament brand you get throw it in the kitchen oven on the max temp the spool can handle overnight for at least 8hrs (you can’t over dry it) then throw it in your Sunlu s2 at the max temp 70c while printing and you should be good to go! I’ve had great results doing this! It sucks because Bambu wants you to pay $100plus for their HT dryer when the AMS 2 pro should do pro like things and dry while printing 🤦🏾‍♂️ but whatever lol!