Something you can't go without and a substitute never quite cuts it.

Any major brand soda, the imitation versions suck.
Other imitations/alternatives- good vs bad
Hamburger vs soy burger
Edelbrock vs chinesium
Real tits vs fake tits
Butter vs country crock
Name brand headers vs house brand
Good head vs bad head
Name brand chips vs Generic chips
Name brand cereal vs Generic cereal
Silver dollar nipples vs pancake size nipples
Name brand tools vs cheap crap tools
Could name a few more.