That’s an option. Both exercises train pectoralis major, anterior deltoid, and company. But pec flyes are a single-joint exercise and fail to hit the triceps brachii, which does receive a training stimulus during the hex press. Machine pec flyes and cable crossovers can also be more taxing on the shoulders, especially among lifters with functional anterior instability from a previous injury or cumulative trauma. This pathology is discussed in detail in the Benefits section.