I have to agree that the Atrix 2 is a superior value! Beep 13's comments are spot on.
I too got the SGSII on launch day and liked it fine. Once ICS was announced, I became worried the SGSII would not be upgraded in a timely manner. There was also a security flaw which has yet to be fixed to my knowledge and I started to get the sinking feeling that this phone would not be upgraded to ICS a timely manner. I picked up the Atrix 2 last Saturday. I bought it off contract and returned my SGSII to preserve my upgrade.
I have owned the Captivate, OG Atrix prior and like the build quality of Moto over Samsung. The OG Atrix was updated 4 times in 8 months the Captivate once at the 9 month mark.
While the SGSII does have some advantages they are not overcome by the price hence my value comment.
The Atrix does feel better in the hand to me. It just feels more solid! I guess I've become accustomed to the higher resolution on the Moto phones because the icons on the Samsung looked so big! They both have some bugs but the Samsung has a lock sceen pin bug and a data gobbling AP News widget. In the 3 weeks I owned the SGS II, I used 1.8GB of data. I do have unlimited data but have never used over 1 GB before. If you do not have unlimited data, beware of that issue. Also I have not noticed any difference in practical speed when using both phones. Both are fast and fluid in all operations. I must say I like Touch Wiz better than MotoBlur but both versions are manageable now and I can even go without launcher pro on my Moto now due to the improved UI on the Atrix 2.
I give the slight edge in the camera and video to the SGSII but the GPS is superior on the Atrix 2. Also the Atrix 2 has a dedicated camera button which I really like. I also like the fact that the Atrix has a micro HDMI port that takes a standard micro cable and does not need a special cable to mirror onto a TV. I like to plug into the hotel TV when on business trips and watch Netflix and the Moto makes it easy.
Battery life is no contest. The Atrix is 20 to 25% superior for my usage patterns which was to unplug at 6:30 - 7:00 am and run until about 9 or 10 pm. After a few days of using, I never worried about the Atrix 2 battery running out.
A top reason for me returning the SGSII and picking up the Atrix was the announcement of ICS and living in an LTE market for ATT. I just felt that given Samsung's upgrade record across all carriers that this phone would not get IC in a timely manner. ( For all you SGSII owners, I hope I am wrong)Also here in Texas there are many rumors flying on why the SGSII was not available in Houston or San Antonio/Austin and that is because they are saying they will launch LTE phones after Thanksgiving. Some even say a SGSII LTE version in LTE markets of which I live in one (DFW)
Overall I think they are both very capable phones. For me, the Moto fits my needs at this time better in the value proposition while freeing up my upgrade to see what comes after Thanksgiving or the New Year. With the Atrix 2, I feel fine waiting a bit longer.
PS The Atrix 2 actually has an FM radio!