Finally remembered to search youtube for old arcade game playthroughs - Scramble, Vanguard, R-Type, Zaxxon, Gauntlet, Sinistar, Ikari Warrior, Heavy Barrel, etc. I'd forgotten just how fiendishly difficult some of those games were. In fact I'd forgotten entirely about some of them, Zaxxon and Vanguard e.g., despite having dropped some significant chunks of lunch money on them, a quarter at a time, back in the day.