If you're not collecting games solely based on their collectible value to others and plan to asctually play them, then the PC Engine is the cheapest and best way to go. You can buy games like Dungeon Explorer II, Dynastic Hero, Ys I & II, Ys III, Valis II, Valis III, Super Air Zonk cheap and they're all 95+% as playable for gaijins. Let alone all the other great PCE-only cheap games.