My Live and Plus have been, for the most part, great.
I don’t play much music or view many photos but I do watch quite a lot of anime and movies and, since getting the Plus, Netflix.
Visual quality has never been an issue. Most of my BD rips are 720p MKV files with AC3 audio and play back flawlessly. My old anime is mainly AVI files with hard subs, not a lot to go wrong there! They play back great. My newer anime collections are in MKV format with soft subs and, as with the movies, play back without significant issue.
If you encode everything to MKV (or remux), you’ll likely get along great with it. :)
I will comment that there’s not great support for SSA subs, so any styles or positions (and multi-subs onscreen) get ignored. Very frustrating on occasion but not a deal-breaker (I would very much like it fixed but it doesn’t seem to be high on WD’s lengthy To-Do list). Likewise with SRT subs; many PC media players will allow multiple subs onscreen simultaneously (or even allow positioning), despite that being way outside the SRT spec. On the WD players, the newer sub replaces any other sub when there’s an overlapping timestamp.
In the early days, there were some significant MP4 sync issues (rectified in the 1.03.35 Live beta IIRC, and possibly the stock Plus firmware). I remuxed whatever MP4 files I had into MKV and never looked back. Testing some old sync-issue files shows that WD did fix that rather nasty issue though. Newer betas also fixed the MKV Header Compression issue caused by the MKVmerge 4.1.x+ builds.
WD do fix things but it seems to take a little longer than many in the community would like (and I include myself among them, tbh).
There are still issues with MP4 / M4V containers not passing through AC3 audio. To be fair, I believe that’s more to do with the official MP4 spec than any deficiency of the Live.
Other manufacturers seem more willing to implement workarounds to appease the community; WD seem to be sticklers for official specifications, for better or worse.
The Plus has a well-documented Instant Queue Unavailable bug that may or may not strike. The FAQ on this forum includes a quick reset code from Netflix that’s worked for me in the past and got me back up and watching within 5 minutes.
Many people claim that the Live / Plus have networking issues. In my experience, most problems lie with the network itself. All my connection issues could be pin-pointed to Vista doing weird stuff with the shares, with a service crashing, with the LMB bouncing all around the network instead of sticking to one PC. If you set your network up right, you don’t need to worry about networking issues.
Kudos for seeking opinions before purchasing. Too often, people blindly buy a Live or Plus and are then disappointed (sometimes understandably) and they come here to complain. If you know what the unit is capable of and accept its flaws, it’s actually a really nice media player. :)
And welcome to the forum! If you do decide to get one, there’s a lot of help available here. If not, please post back and let us know what you eventually purchased.