DELL Latitude E5520 and Dell Latitude D520. Which one would you prefer?

Dell Latitude E5520
Processor: Intel Core i3-2330M (2,2 GHz, 3 MB L3 cache)
RAM: 2 GB DDR3 (1x2GB) up to 8GB
Hard Drive: 320 GB SATA 7200rpm
Graphics Card: Intel HD Graphics 3000
Optical Drive: DVD + /-RW SuperMulti DL
Display: 15.6 LED TFT HD (1366 x 768)
Wired Network: 10/100/1000 Mbps Gigabit Ethernet LAN
Wireless Network: Wi-Fi 802.11b/g/n
Speakers: Stereo speakers Embedded
Bluetooth: YES
Camera: Built-in WebCam
Card Reader: YES
Ports USB: 3 x USB 2.0, 1 x eSATA / USB
Other Ports: Firewire
Video Output: VGA out, 1 x HDMI out
Battery: Li-Ion 6 items
Operating System: Free Dos
Warranty: 3 years by delegation

Dell Latitude D520
Processor: Core 2 Duo 1.66 GHz
RAM: 2048 MB, DDR2
Hard Drive: 40 GB, SATA
Optical Drive: DVDR / W
Battery: Lithium
Display: 14 “TFT
Communications: Modem, Ethernet, WiFi, Infrared, Firewire
Ports: USB, Serial, Svideo
Free Software: Pre-installed Linux operating system and LibreOffice and many other programs
1 year warranty

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