I just purchased a Mustart 26amp portable for $309. While I might take it with me on very rare occasions, for the most part it will reside in my garage as a fixed EVSE. I think using a portable EVSE in this manner is fine provided it's not exposed to weather and the plug normally remains in the socket. I would not be comfortable planning to use this unit if it needed to be plugged and unplugged on a regular basis.