In the field of metabolic and bariatric surgery, Roux-en-Y gastric bypass and one-anastomosis gastric bypass are the two most widely performed bypass procedures. Choosing between these operations remains a challenge both for patients considering surgery and for clinicians making procedural decisions. This commentary provides a structured appraisal across multiple dimensions, including procedural principles, available evidence, advantages and limitations, indications, outcomes, and complications, with the aim of informing clinical decision-making and offering expert perspective.