The definition of durable is "able to withstand wear, pressure, or damage; hard-wearing.
"porcelain enamel is strong and durable"" which does not seem to apply to common laptops. Those Panasonic and Dell Toughbooks are better but you could still wear out a battery if you used it daily.
700 for a 4GB laptop seems high. From the list at http://www.amazon.com/Best-Sellers-Computers-Accessories-Laptop/zgbs/pc/565108 I'll skip down to a 700 dollar laptop which is this Asus:
http://www.amazon.com/Zenbook-UX305FA-ASM1-13-3-Inch-Ultra-Slim-Aluminum/dp/B00SGS7ZH4/ref=CNET
That has 8GB RAM, 256SSD and 10 hour battery time. Seems a better deal. The smaller size isn't too small and that plus the lower weight might help it last a few years more.
Bob

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