I think the comparison can easily be nudged in favour of conventional aircraft technology if more modern, high efficiency turboprops are used for shorter haul flights instead of twinjets. As for costs I agree that swapping out electric motors is not a big deal, however, finding and swapping out questionable batteries and their associated control hardware might be a lot more costly than anticipated. Are we going to see a rate of refinement in electric propulsion similar to these last 15 years or so? I think the “low hanging fruit” has already been picked and the development curve will more resemble a flatline than an asymptotic curve. We’ll see, don’t hold your breath on this one.