- thin bezels around both screen and keyboard
- small but still productive 12" width
- 3.4 lb as light as Ultrabooks
- 10 hour long battery life
- powerful Intel i5 CPU with QuickSync for realtime HD 1080p encoding
- IPS matte screen free of haze often seen on matte screens
- Very quiet fan and runs cool
- can often be found on Lenovo outlet for less than $500
- built-in WWAN for 3g and 4g connection
Built-in WWAN is an expensive $180 option though. Fortunately, antennas are already there, all you need to do is buy a WWAN card on ebay for $10, open the case and insert it into the slot. It is a fairly easy job as showing in this video, thanking to the very thoughtful design of Thinkpads.
There is one little hassle though: there is a white list in BIOS. If your WWAN card is not on the list, then your Thinkpads won't even boot! The good news is you can find a modified BIOS to enable virtually any WWAN card. The one I use in my x220 is "Lenovo_x220_8duj17us_8DET61WW_1.31_NWL", modified by Serg008 (http://forums.mydigitallife.info/). So far no any problem at all.
I first tried a Sierra MC8781 card (GSM), x220 did not see it at first. Then I taped its pin 20 and it worked like a charm. Re-connecting is very fast after sleep or hibernate.
Then I tried a Novatel ES720 taken out from an USB720 modem (CDMA). No problem at all, no need to tape pin 20. As always, Novatel's Windows 7 NDIS driver sucks, it breaks sleep mode (no such problem with XP).
I want a WWAN card that does both CDMA and GSM, so I can use either Veriozn, Sprint, AT&T or T-Mobile. The Gobi cards do that. Gobi2000 seems the best choice for now for only $10, because Gobi3000 is significantly more expensive and does not offer much more. Gobi4000 supports LTE, but not cheap neither and not so clear if x220 supports it or not.
The Gobi2000 I got on ebay is pulled from a Toshiba Satellite L645; so I downloaded the driver from Toshiba's website. Note: Toshiba got the dates wrong, be sure to get the V1.1.140; the V1.1.120 gave me DOBS.
To support all CDMA and GSM networks and carriers, Gobi2000 uses dynamic firmware which is loaded after every boot, sleep or hibernate. A list of firmware can be found here. For example, Verizon firmware is found in folder 1, AT&T in folder 2 and generic GSM in folder UMTS.
My Gobi2000 card is made for Verizon, therefore it always download firmware from folder 1. To let it download AT&T firmware, I move files from folder 1 to somewhere as a backup, then copy files from folder 2 and UMTS into 1. I then sleep x220, when it wakes up, it'll load AT&T firmware and connect to AT&T. When I need to go back to Verizon, I simply copy the original files back to folder 1.
As you realized, Gobi2000 takes much longer to re-connect from sleep, because the firmware must be reloaded each and every time. Quite a stupid design, there must be a better solution than this.
Speed is very good, seems the internal antennas do a better job than the one on USB modem's. Built-in WWAN is something once you have, you never want to live without, even though WiFi is widely available these days.
A note: once the driver is installed and Windows 7 has seen the card, you need to do a reboot for the NDIS (Mobile Broad Band) network adapter to be installed. It is always on like WiFi, you don't want to use DUN.
How to turn off WWAN
How to turn off WWAN