Verdict
Q1 Pro is QIDI's 60°C-heated-chamber CoreXY at $449 — meaning ASA, ABS, and even some polycarbonate work without modification. P1S is $699, no heated chamber, but ecosystem polish and AMS support.
Buy the Q1 Pro if: engineering filaments are the goal (ASA, ABS, PC), budget under $500, OK with QIDI's smaller community vs Bambu's.
Buy the P1S if: mostly PLA/PETG with occasional ABS, want AMS multi-color, prefer Bambu's mature firmware and farm-management features.