String Trimmers Buying Guide: Everything to Know Before You Buy

A brushed motor uses physical carbon brushes that wear down over time and create friction, generating heat and reducing efficiency. A brushless motor uses electronic switching instead, which runs cooler, lasts longer, and draws less battery for the same output. Brushless motors, like the one in the EGO ST1521S, generally cost more but hold up better under regular use.

0.065 to 0.080 inch line handles typical lawn grass and light weeds. 0.095 inch or thicker is better for dense weeds and woody stems, provided your trimmer's head is rated for it. Using line thicker than your trimmer is designed for can strain the motor and reduce line feed reliability.

Only if you're likely to add an edger, pole saw, or brush cutter down the line. Attachment-capable trimmers, common on gas models like the Husqvarna 128LD, cost a bit more upfront but can replace buying separate standalone tools later.

A well-maintained battery trimmer from a reputable brand typically lasts 5 to 8 years of regular residential use, with the battery often needing replacement before the motor does. A well-maintained gas trimmer can last 8 to 10 years or more with regular carburetor and air filter service, though gas engines require more consistent upkeep to reach that lifespan.