Ask what guns the pros run and the full answer fits in one breath: two Mod 15 configurations and one MPC build. That's the entire competitive meta as it stands — every AR player in the league on one of two near-identical setups, every SMG player on the same one.
The mechanism is the GA system. On top of the official CDL ruleset, the teams collectively agree to ban attachments and weapons they consider unhealthy for competition. By the time the bans settle each season, the viable pool is tiny — which is why our classes page is short. It isn't a sample of what pros use. It's everything they use.
The two Mod 15 builds differ on a single meaningful axis: the Quickstep Foregrip build (run by Huke, HyDra and Cellium, among others) buys movement speed, while the Fusion Barrel build (Dashy, Scrap, RenKoR) spends that slot on the barrel instead. Same sight, same grips, same stock. The choice tracks role and preference, not correctness — the familiar CDL story of convergence at the boundary, freedom inside it.
Both builds and the MPC's single class are on the classes page with import codes, so you can run the exact configurations without transcribing anything.