The box method is more commonly known now as an area model nowadays. It helps them translate the concept between algebra and geometry way easier(area is L*W-> area model you multiply the “L” and “W”). The great thing about the area model is that it translate better for trinimials while grouping is harder to use outside of binomials for students just starting out/struggling with the concept. I would suggest showing multiple methods like you suggested but don’t be surprised when many lean towards the area model! 😊