I can't speak for the Panasonic, but the LG isn't very good for streaming local media in my experience. I just acquired a Sony BDP S590; it doesn't seem to support SMB/CIFS sharing like the LG, but the DLNA functionality is much more reliable and user friendly. The BD670 would choke using 10-15 Mbps 1080i .TS files in my collection over Wi-Fi and even on my wired MoCA connection when I wasn't using one of the more recent firmware updates. Additionally, when using DLNA it would frequently throw me "Server Error" messages after stopping playback of a file, causing me to have to constantly refresh of the list of servers and navigate back to the directory I wanted to view to continue viewing files within a folder. (Several other LG users on the Serviio forums reported the same issue.)
The Sony plays those 10-15 Mbps files without difficulty over Wi-Fi, provides an interface that makes it much easier to read long tiles and doesn't seem to have the bugs that were causing all of the server errors. Not only that, but it has allowed me to fast forward and rewind the files I have tested thus far (what a concept!) and it allows me to view details about the file during playback (bitrate, file type, etc.) Sony established DLNA, so it makes sense that they would do it well. I didn't realize what I was missing when I was operating within the LG world.
I've had the Sony BDP S590 for about 3 months now, and it also has its cons compared to the LG:
- You get Cinavia, which prevents you from playing backups of your own blu rays.
- Won't play a number of MKV's and other files that the LG would play.
- Won't give you the option to change the drive letter if your USB media has more than one partitions
- Does not have a zoom feature that is helpful when you want to zoom widescreen 3D Blu Rays (Of course, my TV has a zoom feature but does not work in 3D).
- I have exactly the opposite experience with Sony's DLNA over Wi-Fi than yours. Almost every file playing would freeze after a minute or so, so I have to use the wired connection.
- Remote is kinda cheapish - the cover of the battery is annoying me from day one, the rubber arrows almost get stuck sometimes.
- Sony's HDMI CEC is compatible only with Sony devices, meaning you can't control other brand devices with the remote as you can with the LG.
The LG also has lots of problems, so I guess there is no ideal Blu Ray Player out there yet.