⭐⭐⭐⭐⭐ For 2025 lab study: ⭐⭐⭐⭐ For modern production: ⭐ (not recommended)
If your lab focuses on CCNA/CCNP R&S (routing only), 12.4(16) is perfect. For CCIE security or DMVPN Phase 3, move to 12.4(24) or 15.x. c3640-jk9s-mz.124-16.bin