I recently upgraded fromt he MIFI 2200 to the MIFI 4510L. I live in an area with no LTE around. I immediately had a lot of problems with the MIFI stalling on the 3G connection. I have a Windows 7 laptop. I eventually saw that others were having trouble with the 4510L and Windows 7 so I forced the 4510L to use wireless b/g instead of N and the stalling went away. I am now travelling in 4G territory and this this is awesome. I am consistently getting 20/10 bandwidth and I have had no stalls. I am thinking that the 4510L needs a firmware update for wireless N. Otherwise this is amazing.