I really wanted LTE to work, I was excited when I saw the samsung and the novatel at CES. I bought the Samsung day one and it could not get it to work for more then 2-3 minutes at a time in the Las Vegas convention center. My old 2200 worked great under these circumstances. Swapped the Samsung for the 4510L and had the EXACT same experience. In Chicago, Philly or Vegas at a trade show it was worthless. If I pulled the battery I could get another 2-3 minutes before it locked up. Seemed ok in Hotel rooms so if you are walking around or if there are lots of wifi signals around it simply does not work. I just transferred service back to my mifi2200 as I NEED internet access when attending trade shows. I kept the 4510L. I am hoping it is a firmware issue or Verizon will eventually unscrew the LTE network.
I tried setting to 3G only as well as changing channels. Nothing helped. Sometimes I am reminded that there is pain with being an early adopter
I figure I will check in every three months and see if anyones experience has improved.