LTE is not true 4G. Like all other technologies out today, they're officially allowed to be called 4G by dispensation from the standards body that governs use of the term, the ITU. This is so because they kept going in circles on the spec definition and US carriers decided to just get to work. When Sprint went with WiMax that was expected to be the 4G standard and while they were building, the ITU went back to the drawing board and changed their mind.
Actual 4G as specified (now called true 4G because the blogosphere won on the use of the term, not stated in the original spec) is 100 Mbps downloads using either LTE Advanced or WiMax 2. There are no deployments of it in the United States.
A lot of people rightfully believe that their LTE speeds are much higher than they actually are, because the Speedtest app that most people use is highly inaccurate above a certain point. Don't quote me because I am going from my imperfect memory, but I think that you can forget above 25 Mbps.
After a certain point, you can forget the Mbps spec you have because it stops dominating the network performance.
What you care about and what few discuss is the lag time between packets, indicated by the ping time.
Network data is not a stream of bits. If it were then only Mbps would matter. Network data is a stream of packets. Each packet is less than 2000 bytes long, and there is a transmission delay between each packet.
I have been in locations where I tested better than 4 Mbps on 4G and 1 Mbps on 3G and the 3G was hilariously faster - lower packet delay times dominated.
1x speed for a Blu-ray disk is 36 Mbps. Unless you have a plan to flawlessly stream high quality, high definition BD movies over a mobile connection, I don't think that you'll really need all that much in the way of absolute speed.
What will govern your performance is low delay between packets and how quickly and efficiently the phone gets those from the antenna, through a massive amount of software and hardware, and onto your screen.
It's really not about the Mbps after a certain point, depending on your use.
For web browsing, 2 Mbps with low lag (delay time) is actually pretty ok.
Put it this way - on city streets within the law, a 10,000 horsepower car doesn't really out-perform a nice car. Not every number matters.