i will be switching in febuary also (upgrade time for my personal phone) mainly because the 4g (LTE) phones running andriod 3.0 should be out by then. We had one X at work last week everyone got to play with. to me it seemed ok in size in my hand but when i put it up to my head it felt like i was talking on a netbook or small laptop.
i do have the best of both worlds though, the incredible is a perfect size for those that do use the phone but still send alot of txt or emails and screen on the incredible is gorgous (more on that in a second). however if you are heavy data user and not much phone the X's screen size can't be beat, so for a work phone where i will be sending alot of emails the X will be awsome. Also one thing i noticed is even those alot of motor blur is easily removed i am not a fan of the motorola launcher, but this is android so that is easily fixed with a launcher pro download from the market. on the incredible though Sense UI is really nice and makes daily use visually appealing and really slick, it just makes alot of well,,,sense. One thing i noticed immediatly with the X is that it isn't as big as it looks in pictures and they did a great job on the buttons and making the phone mostly screen with minimal bezel (however personal gripe is that the menu and home key are in opposite places than the incredible, you can imagine how that gets to be annoying between the two phones). the X feels great also, just feels like it is built really solid, the incredible not so much but the incredible does look fancier. as for the screen, everyone at work here was excited about the screen on the X then someone asked me to my incredible up next to it, the X is so noticably bigger but then i turned the screen on. the X's screen looks great until you put the incredible next to it, then it looks very washed out. the AMOLED screen of the incredible is very bright and has amazing vibrant colors, the X looks great also until it is next to the incredible then the colors looks stale and washed out.
as for the one handed, i am the same way. i rarely use a smartphone in landscape so i always use it one handed (yes i am a huge fan of swype and similar keyboards). the incredible is perfect for one handed use you can very easily get to any part of the screen with your thumb no matter how you hold it. the X i could get to every part of the screen but it was a slight stretch to get to the upper left without changing my grip on the phone, was it a problem? not in the least so i found the X to be easily used one-handed and having swype pre-loaded saved the 5 minutes of hunting down the apk.
just my little mini-review both phones absolutly rock and it really does come down if you can handle the size or not. BTW the X fit in my back pocket just fine.
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