I just tested the The new AT&T Sierra Wireless AC881 with the Top Global MB6800. With the initial test the card would not work. It had the same issue as the AC875 where the 3G light would go in and out and not keep a connection. I updated the internet access category after logging into the router and inputting this information under the phone number: *99#. After rebooting the router the 3G light came on and stayed on. I did a speed test through speakeasy.net and got these results:
Download - 1703k
Upload - 240k
I also did a speed test with the card in directly in the laptop and got these results:
Download - 1612k
Upload - 359k
I was thoroughly impressed with the speeds and even more so that it works great in the router with minimal tweaking.
Here is a pic with the Sierra AC881 in the TopGlobal MB6800 with the power light green, the WLAN green, and the 3G green.

Here is a screen shot of the speed test with the AC881 in the MB6800.

Here is a screen shot of the speed test with the AC881 directly in laptop using the communication manager 6.5
Download - 1703k
Upload - 240k
I also did a speed test with the card in directly in the laptop and got these results:
Download - 1612k
Upload - 359k
I was thoroughly impressed with the speeds and even more so that it works great in the router with minimal tweaking.
Here is a pic with the Sierra AC881 in the TopGlobal MB6800 with the power light green, the WLAN green, and the 3G green.
Here is a screen shot of the speed test with the AC881 in the MB6800.
Here is a screen shot of the speed test with the AC881 directly in laptop using the communication manager 6.5
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