Well, purchased the SV Journey after getting the v2450gps last year. Wanted to make sure the FACRESET.TXT would work and manually updated all three firmware. Then did Factory reset. Everything now works great. The transmitter wouldn’t update its firmware until I did all this. In fact, the video viewer 2.0 wouldn’t even connect to drone. The firmware prompt has now disappeared. Also updated the transmitter strength fro. 5 to 8 in the web ardupilot interface and increased the strength used to transmit the packets to 7.5. Increased the vertical speed to 800 cm/sec/sec assigned by pilot.
But the most striking difference between the 2450gps and journey is the increased GPS speed and stability.
And as I understand it. version 3.6 of arducopter is preloaded.