I feel like they are overrated if you live in a city and fly to other cities and never find yourself in very rural areas or the midwest/west in general. In that situation most every carrier is going to perform well and you are spending extra money on Verizon (in most cases) so that they can provide towers to rural america. I know they get the highest speeds in a lot of cities too according to root metrics, etc. but what does that really matter. It's a mobile phone, anything over 5 mbps is capable of doing most anything on it, and with capped plans you can't use the hot-spot to download torrents or anything.
Now, if you happen to live in the heartland or out west (Kansas, Colorado, Oregon, Utah, etc.) I feel like Verizon would be a smart choice. I live in Illinois and do a lot of rural traveling. I carry Verizon, AT&T, and T-mobile sims for testing purposes and find that Verizon outperforms the others in rural areas period. In town the other two have more towers and offer a more consistent indoor experience. It's a trade-off, but I'll take a signal over no signal any day whether it's 2G,3G, or 4G. This is all based on general knowledge that I've read/experienced over the years. I know there are specific cases where in the middle of downtown Chicago Verizon may be the only carrier that can penetrate a building and offer service; however, in general they will all be fine in major to mid-sized cities.