As of course you realize there are way too many variables to generalize. First there is how much you drive every day, then there is the cost of electricity in your area (and what times of day you charge). There is also the cost of installation (cost me $500), which varies a LOT depending on local needs. Finally, of course, there is the convenience aspect .. is is worthwhile convenience having faster home charging even if there is some additional outlay?How many years of 'inefficient' charging will it take before it equals the installation cost of a dedicated 240V line, breaker and Tesla WC?
And btw the “inefficiency” here is not small .. I’ve forgotten the actual numbers (there are many threads here discussing this) but with a cold battery you may not get ANY charging for quite some time after plugging the car in. We’re talking DOUBLE the electricity costs in some cases.