I recently changed over to an Alpine HU from a cheaper Sony HU. They both have USB ports. I don't notice any sort of loss of sound quality between the Bluetooth and the USB plug. Having said that, I find that the USB port is GREAT for using a flash drive with your music, rather than plugging your phone into it. I can't get my new phone to charge (or connect) via the Alpine USB port right now (I haven't messed with it too much). I do get a screen on my phone (Nexus 4) that asks what kind of connection I want to make, but the radio never makes the connection and eventually 'times-out' and displays a error message. I really need to try to connect to my old phone (Samsung Exhibit 4G) and see how that works. That will let me determine where the problem is (radio or phone).
Crutchfield has great customer support, includes the adapters, and is guaranteed to give you a factory warranty. Some of the sellers at places like Amazon aren't 'authorized resellers' so you don't get a warranty. My rule of thumb is, if the savings are almost %50, then I'll buy elsewhere. I bought my Infinity speakers from Amazon, but only because I could replace them again if one failed and still be near the original Crutchfield price (so the warranty didn't matter any more).
Ohh, I just saw your links now. Let me tell you that I don't suggest buying such an inexpensive car stereo. The reason I changed out the Sony for the Alpine was because I should have spent more money the first time around. I bought a Sony with 2 Sony 'Xplode' speakers. After installing it, it sounded 'okay'. So, I bought Infinity front speakers. It sounded better, so I then bought a 4 channel amp and Infinity rear speakers. It sounded great, but was lacking bass. So, I bought a Sub-woofer, Mono amp, and Alpine HU. Now the system sounds AWESOME. It connects to my phone almost as fast as I can get in and start the car. I can control the music from the HU or the phone (VERY important if you live in a State where using your phone (even as a music player) can get you a ticket)!
Take a look at this Alpine:
http://www.crutchfield.com/p_500CDE147B/Alpine-CDE-147BT.html#details-tab
While it is almost twice the price from Crutchfield, it is a much better stereo. It features 6 Pre-amp outputs (vs. 4 from the Sony you picked). I think you are likely to want to upgrade the stereo system more as time goes by (like I learned). Not having 6 outputs could limit your choices later. The Alpine also has 4 Volt preamp outputs (vs. 2volt from the Sony). Simply put, having 4 volts gives the amp a better signal to amplify, because, amplifying crap just gives you more crap. As an added benefit, the Alpine will have a bit of resale value. I don't think the Sony will hold up nearly as well. As a bonus, you get a 8GB free flash drive from Crutchfield. You might very well find you don't use your phone nearly as much, once you start playing songs from the flash drive. Just be sure to set the stereo to 'random' play the music. In the beginning, my stereo would always play the songs in the same order. Then I learned that you have to select 'random' play....
EDIT: I should mention that a co-worker had problems when he was installing an amp that he bought from Crutchfield. On a weekend, he called the free tech support and they walked him through the problem. Just another thing to consider.