It works great for me, I have it configured for every device in my house. Set it up with four TV's (Insignia, Panasonic, Sylvania and Samsung), Sony Blu-Ray player (really old school too, one of the originals), Comcast Cable box. I even set up a custom remote for my MacBook Pro but only play/pause and volume controls worked...have yet to go back and reprogram it to see if everything will work.
I set up a custom remote for my Insignia TV with only the buttons I use and it works great.
If the custom presets for each TV don't work then try learning it from the original controller you have - I have found that it works very well this way. Just set the controller a few inches away from the phone and line up the IR ports. After you create the controller layout with the buttons you want, it will prompt you to hold down the corresponding buttons on the original controller and the app will read the IR signal and store it.
This is by far one of my favorite features of this phone. Besides of course the 2.26 GHz quad core processor and 2GB of RAM. I ALMOST went with the S4 and then I noticed the IR app on the G2 as well and there was just no looking back. I love the looks I get when I control my TV with my phone lol.