Cheap home espresso machines make espresso that tastes just as cheap. The $170 Mypressi Twist doesn't.
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If you want decent espresso at home, the endless series of upgrades and hacks you'll run through make it more like a marriage than a drink, as Ninth St. Espresso's Ken Nye puts it. An espresso machine has to deliver on two variables: Temperature and pressure. The basic home espresso machine fails pretty miserably on temperature stability—something like 10-20 degree swings, when you typically need a stable 195-205 degree temperature for proper extraction.
Mypressi Twist Review: Home Espresso Dynamo (http://gizmodo.com/5707531/mypressi-twist-review-home-espresso-dynamo)