I've been going through a variety of 4G cards in the past couple weeks, trying to find the absolute best device and service. I started with Verizon but had some trouble (turns out I had a defective Samsung device). The replacement worked okay, but I wanted to make sure I had the best. So despite getting 8mibs speeds both download AND upload, I switched to Sprint.
Well Sprint is a total joke. Not only is their 4G coverage terrible in my area (I only got 10% signal strength in a decently populated area in Tustin, CA), but it was horrible in L.A. I had dinner in Beverly Hills and the coverage there was underwhelming. My tethered Verizon iPhone had better service. And that's a bummer, because I was rooting for Sprint.
Less than 24 hours after acquiring the Sprint device, I replaced it with an AT&T hotspot. The coverage looks promising. However, I ran a speed test and got these results:
There are a couple other carriers like T-Mobile and Clear, but without even trying them, I doubt they'd do much better than AT&T, the 2nd place winner in my books.
So it looks like Verizon's 4G network is the best in Orange County. The coverage is acceptable and the speeds are just outstanding.