I got the Atrix 4G on pre-order so I paid full price. CES device of the year in 2011 if I recall correctly. I was so excited to have the latest and greatest (ha ha). I was even able to convince two coworkers to buy it. I proceeded to buy the regular dock, car dock, and even the lapdock. The hype and expectation of this device however was very short lived. Be it poor marketing from Motorola, the timing of when Verizon launched their 4G LTE, AT&T's terrible commercials or locked bootloader and lack of speed in their 'blazing fast' HSPA+ 4G, or some other long-forgotten reason, it really just killed this phone and Moto's apparent desire to improve upon it.
And how long before Atrix 2 was released? Why did Moto reverse the lapdock ports so new phones won't work on the Atrix lapdock? This phone was supposed to launch Motorola in a new direction, but instead, it proved that they didn't work out the kinks in time. It seemed as though this phone was a big "whoops, nevermind". Whatever the reason for the flop, it seemed to result in Moto not putting the CES 2011 pick on their priority list. The few updates we got didn't exactly take full use of the true capability of the phone (at least for it's short lived 'time'). But all in all, it worked fine for me. Except for the drastic overheating, random reboots, and other pesky things which didn't make this phone suck, but it didn't make it shine either. It was just... meh. At least for me.
Since I've owned it, I discovered that Motorola doesn't put the "human experience" into their design intent very much. The location of the cable when the phone is plugged in makes it hard to handle and use. The car dock keeps falling off the dash. The standard dock makes the phone hard to use if you want to listen to music... the original software allowed for a nifty widget to show up on the dock interface, but it was later removed. The alarm ringtones are... let's just say not comparable to those on the Galaxy S II. When it's in my pocket and I'm reaching for it, I can't tell which was is up. Of course, your individual results will, most certainly, vary.
Having had a chance to use ICS on a S II Skyrocket and seeing how Samsung really makes an effort to make Android human-like (lawsuits aside), I would've really liked to see my phone take advantage of similar nifty features. When the Skyrocket got the update, it didn't change the phone into something phenomenal... just something that was even "niftier" to use. Capabilities between the two phone though? The same. At least for an average user.
All in all, Android 2.3.6 can be just fine provided Motorola lived up to the hype they created. This phone was never anything more than a regular Android phone when compared to all the rest which were released in the same time frame.
Again, your results may, and likely will, vary. This is just my two cents. And the reason why my next phone will be something other than Motorola.