I had a MIFI 2200 for years and it was rock solid. I replaced it with the Samsung Hotspot and then swapped that for the MIFI 4510L. The 4510L is better but both 4G/3G devices have a lot more problems than the old 3G only MIFI 2200. I am in an area with no LTE and I use 3G only unless I travel. Does anyone understand why the performance is so much different? It appears that since this is an LTE device on a 4G plan that I am using a different network than an old 3G only device. Does this make sense? I will be cruising along fine on the 4510L and then all of a sudden I get a stall and pages time out and then it takes off again.