Those lucky enough to own or play a 1960s or ’70s-era Guild acoustic flattop remember them as solid workhorses that sounded great and got the job done. Fast forward to the present and the recently relaunched Guild is revisiting the past by reissuing the M-20, the guitar that was the first off the assembly line nearly 50 years ago when the model was introduced in 1967 at the company’s Westerly, Rhode Island, plant. With its concert-sized body and sleek design, the new M-20—some call this short-scale model the Nick Drake guitar since it was featured on the cover of that late folk artist’s Bryter Layter album—seems more a work of finesse than a workhorse.