I tend to agree with you. I still have my SG5 on and look at both it and my iPhone. When there is a discrepancy, I trust the GPS.
I think we are becoming overwhelmed with all this technology. GPS, Laser and now Phones. I admit I am a gadget guy and I want to have all the cool new devices, but, I also understand that these devices are not going to make me a better golfer. That is still left up to me. It is still my decision whether I am going to dedicate the time to improving.
These devices are just tools. Personally I am not at the point where I need to worry about my phone saying 120 yards and my GPS saying 123.
It has happened on a few occasions where I have labored over the distance of my approach shot only to hit it fat or thin.
My point is, use the devices for what they are, tools. Find one you like and use it. Generally speaking, I use my GPS on shots of 130-150 yards out, and my laser for shots 130-150 yards in.