I'd recommend trying to figure out what doesn't work right between install and liveUSB. 95% of the time in my experience that's due to non-free packages being available on the liveUSB, but not being enabled during or after install. If your issues are related to a specific component (Wi-Fi, graphics, etc.) then it's probably something that needs third-party or non-free sources enabled.
There's some sort of deal where a distro can't just install non-free drivers due to licensing without you agreeing to use them, so they add a question or option to enable those during install in order to use them. They can have them enabled in the live USB for some reason. You can also do that after install by poking around in your repository selection.
These are pretty simple things to investigate once you're used to using Linux, but certainly a bit overwhelming for someone new.
What distro are you trying out and what are the issues you're seeing between preview on USB vs install?