Different strokes, different folks. I buy all my phones new and outright, no contracts, and I buy top of the line and get a new one every year or so. My phones of choice since 2012 have been the HTC One X, HTC One M7, and HTC One M8.
All three phones are still working fine, and all three still look great, especially considering I don't use cases or covers.
But if you have something on the lower end of the HTC scale, you've got a phone that costs $200 and you're comparing it to a phone that costs $700 and up.
Are you and your son on the same carrier? That can make a HUGE difference...here at home, I get solid Verizon voice and LTE, but pop in an AT&T or T-Mobile SIM and I'm lucky to get 1 bar voice and drop down to 3G data.
And finally, Apple has been known to "cheat' on the signal strength meter.