We have it - replaced Time Warner just after Comcast gutted them out.

Installation didn't go very smoothly. They initially verified that I had signal to the distribution box down the street, and assumed that signal reached the house. (We no longer have regular phone service - cellular only.) The signal didn't reach the house due to a cut cable in the backyard. However, they were determined, and we did get everything up and running by the end of the day. Took every bit of 6 hours to get the job done.

Internet speed (paid for highest package 5mb down 1mb up) is as good or better than what we had with TW.

One of the things I don't like about the service is that they want to come out and install any additional boxes for you. You can't go to an AT&T Uverse store and pick up a box and plug it up like you could with cable.

Had some problems with pictures stalling. Had AT&T come out to install an extra box for an additional TV, and while the tech was there I asked him about the picture stalling. He went from TV to TV at all the connection points and checked and re-terminated several connections. Plus he replaced most of the wall jacks with newer items. His statement was the service is very fussy about signal quality.

Haven't had a single stalled picture since. His 1-hour install-a-box-and-go turned into a 4-hour schlep through the system. Real dedication to customer service there.

One thing they don't tell you about is that you can't watch HD programming on more than one TV at a time. Occasionally, while browsing through the channels we'll get a popup on the screen that tells us of that limitation. I've yet to figure out what's triggering it, because rarely do we ever watch more than 1 TV at a time, and when you switch off the TV, the cable box turns off, too.

A serious limitation of the service, far as I'm concerned, is that the tuner boxes won't stay powered up without a TV connected and ON. Even then, they won't stay powered up for more than 24 hours. We have a whole-house audio system that we used to feed from a dedicated digital cable box to get the commercial-free music channels. Audio-out to an amplifier, which is connected to a impedance-matching box that feeds the rooms in the house. Almost every room has speakers with a local volume switch. We leave the system on 24-7.
Got a separate AT&T box to serve that purpose and discovered this little annoyance. Tried to trick it by plugging in a cheapo LCD TV and leaving that on - still cuts off after 24 hours. Solved the problem by ditching the AT&T box in favor of Sirius via PC - still get periodic interruptions, but not as bad, and the PC has to be on 24-7 anyway.

Overall, we're getting far better service and many, many, many more channels than we did from TW, all for about the same $ every month.