Cisco Switch Simulator What Is The Best Cisco IOS Simulator?

What is the best Cisco IOS simulator? - cisco switch simulator

I have a small laboratory at home w / 5 routers and 3 switches. However, I travel a lot, and I would like for the CCNA / CCNP study, while on the road. I have many software-based Cisco router simulators times to ask what is the best, before spending much money.