This film sets out to do its thing and then sticks with it. In terms of a film experience, most of what I didn't like was almost certainly intentional in its mimicking of films from that era. I'm not a fan of those but I can't fault Future '38 for having the integrity to stick with them.
Most of the obvious visual comedy fell flat for me but the film more than makes up for it and is worth watching alone simply for the wonderfully 1940s banter, especially that as delivered by the two leads.