Hate to admit this but I work for the Phone Company. ATT does not make the phones. It is a licensed product and I believe it is built by Uniden. Kind of like Whirlpool building Sears Stuff, MTD building Cub Cadet stuff.
I have a few of the ATT Products and they work well. But I also have Panasonic and Sony and they work well also.
Every phone used by the ATT "The Bell System" Company used to be built in Indianapolis by Western Electric which was the Bell System's equipment builder and also owned by ATT.
Then came the break up of Ma Bell. Other than one Business Phone System built in Shreveport, everything got farmed out overseas. I am sure that is also gone now.
Long Story Short, Buy It, Try It. If you don't like it take it back. ATT has their name on it. They will stand behind it. They don't want anyone trashing their name. Their Officers are the only ones who can do that and they are real good at it.
Good Luck,
The masked phone guy.