Just thought I let others know about the new updated Version. I have the M4, and that was at the 2.9 version, and now it's at 6.1. According to Bel, they adjusted the antenna and upgraded it to the current version of software. Before sending it in, I was getting self cal display. In addition, I have noticed an improvement in the K band distance. There is this area in Orlando that I travel through everyday, and usually I start getting a signal around 1.5 to 1.3/4 miles down the road. In the past few days, I noticed it was receiving the signal at just over 2.1 miles. This is a school zone area with a K band radar that clocks all drivers. Therefore, I think the upgrade made a difference in my radar's performance. I hope someone does a full test soon on this version to see if any other improvements have occured.