Buying tech smartly is difficult. Sam Grobart reduced a lot of hard-earned and complex wisdom to seven rules of thumb in the New York Times. I was pretty impressed with this list because I think his advice is sound and he was able to reduce it to short rules of thumb. Here are his seven rules, each one a trade off, as annotated by me.
When buying hi tech....
* Pay for RAM, not speed. The speed of the computer chip does not matter; the attention-span or RAM memory does matter.
* Pay for messaging, not minutes. On your phone, your texting is more expensive than your voice time.
*Pay for components, not cables. Buy the best components, and the cheapest cables.
* Pay for speed, not channels. For cable internet, with enough speed you can watch TV channels on the internet for free.
* Pay for Applecare, not Mobileme. For Applefans, the Apple insurance is worth it, but their cloud service is not.
* Pay for screen size, not refresh rate. On TV screens, bigger size makes a difference while refresh rate does not.
* Pay for sensor size, not pixel count. On today's cameras you'll have enough megapixels; better quality comes from larger sensors.
* Pay for reliability, not mileage. On a car, you'll spend more of repairs and maintaince over its lifetime than you will on a difference in gas.
* Pay for comfort, not weight. A bicycle's feather weight is moot once you add water bottle, a bag, any extra clothes you wear, while its comfort never disappears.
* Pay for foam, not down. The biggest difference in the warmth of a sleeping bag is the insulation under you, not the down over you.
* Pay for glass, not shutters. In professional cameras, great lenses endure, while the camera bodies change and go obsolete.
From the comments (so far):
Pay for speakers, not the amp. When purchasing a sound system, better quality speakers will make more a difference than a better amp.