Drying filament can help its printability, bed-adhesion, and lessen stringing. Some filaments need drying more than others. PLA can perform better with drying, while PETG will be a stringy mess without it.
Bambu Labs - If you have a Bambu Labs printer, the AMS 2 Pro or AMS HT may be your best bet for features, availability, and compatibility:
SUNLU
Creality Space
Pi x4, with 2×2 layout, is one the best values along with the Sovol SH03) if you need to dry more than PLA/PETG, but don't need >85C (which you'd want a Sunlu E2 for)
Eibos Cyclopes
Sovol
Polymaker Polydryer - this brand is the best under $100 option because of its versatility (1 dryer, many boxes and mods)
Note: There are plenty of dryers that get the job done, but many of them are close in price to better, more modern models. If budget demands the lowest priced options, they're still going to get your filament dry.