Verizon, Sprint, and a few other networks here in the US are CDMA networks which hardly anyone else in the world uses. It does limit the consumer to particular phones and they generally won't work overseas but since I haven't been out of the US in 10 years, it's not an issue. Verizon also has phones available that in addition to using the CDMA network have a SIM chip and can switch between networks.
The last Dell PC I purchased made the
10 Worst PCs by PC World list. Like most manufactured PCs it used proprietary components that were very expensive to buy. When my power supply died, the least expensive price was US$120. The power supply also took the memory sticks and most of the motherboard with it. Instead of repairing the one month out of warranty PC, I took $500 and built a very nice machine which I've since turned into a file server. Yes, it's a little bit of work but I can easily upgrade and replace at a lower cost than with an off the shelf PC.