The big differentiating feature on the SoundPlate is its built-in optical disk drive and Smart TV functionality. At $600, you're definitely paying for those features, as well as the convenience of having it all integrated into a single unit. Wi-Fi is included for connecting to your home network, as well as Bluetooth for streaming audio from smartphones and tablets.
The Smart TV suite includes most of the major apps you'd like to see, including Netflix, Amazon Instant, Hulu Plus, YouTube, and Spotify.
The LAB540W can upscale to 4K, but given that your fancy new 4K TV probably has a very good scaler in it, there's not much point in using the SoundPlate to accomplish this.
If you have a collection of music on a PC or NAS, the unit does DLNA streaming and helpfully lists available servers as shortcuts on its home page.
If you're worried that the SoundPlate's integrated Blu-ray player won't perform as well as a standalone unit, I can put your fears to rest. The SoundPlate performs to the same standard as a standalone Blu-ray player and was able to upscale DVD to acceptable levels, with our "Star Trek: Insurrection" test lacking the moire noise I've seen on lesser players.
Likewise, the LG passed all of the image tests we threw at it for both Blu-ray and DVD. In addition, its speedy wireless connection and decent image processing meant that it was able to present and maintain stable image quality from a test scene of "Lost."
While you can't expect the utmost in high fidelity due to its tiny size, listening to music on the LAB540W was quite pleasant. The subwoofer integrates very well with the main base, and there's plenty of vocal detail and treble sparkle. Only on very rare occasions did the treble become a little ragged.
This thing can get loud, too! At full volume, it didn't fall apart as much as competitive systems could. There was an absence of obvious distortion, and it could easily power a polite dance party in your living room. I put on party anthem "Get Lucky" by Daft Punk and while the song was "there," it sounded unusually urgent, like the bass player wanted to take a break and so was pushing to finish quicker. This probably has to do with the high 24/96 bit rate of the file, as no other music did this.
If you like "talky" movies or TV shows, then the LG does a very good job of reproducing dialogue with a very natural timbre. For the purposes of this test, I compared it to the Sony HT-CT770 ($400 USD street price) sound bar. Using a sequence from "Avatar" (26:53) the Sony sounded more cupped than the LG, almost as if the actors were speaking with a hand over their mouths. The sense of envelopment was a little better on the Sony, but it wasn't of the "ooh, there's insects flying right behind me" kind --more of a surround white noise than detailed effects. With the added thwak of the subwoofer, the SoundPlate isn't completely at sea during action movies, with it delivering plenty of impact during explosions, monstrous animal footfalls, and the like.
While I'm not sure devices like this will take off -- most people already have a disc player or game console --the LAB540W is nevertheless a solid performer with excellent design aesthetics. The interplay between the main unit and the sub is well-integrated and cohesive. If you're looking for something with more pure popcorn thrills, then you may be better off with another sound bar, but the LAB540W handles itself well enough for films and is better than average with music.