Vizio TVs often have weak Wi-Fi chips. Plug in a LAN cable for faster loading.
While Roku is a closed system (harder to jailbreak), it offers a massive app library that far exceeds SmartCast. The Chromecast with Google TV is an even better option for tech enthusiasts, as it allows for some sideloading and offers a pure Android TV interface. jailbreak vizio tv better
Even if a jailbreak existed, it likely wouldn't make your Vizio TV "better." Here’s why: Vizio TVs often have weak Wi-Fi chips