The final problem I found with the 84L9363's pictures materialises when you switch to 3D playback. In many ways 3D pictures look pretty great, thanks to their brightness, vibrancy, and their complete freedom from both flicker and crosstalk ghosting. The size of the screen helps too, making sure the 3D images completely fill your field of view for a truly immersive sensation.
However, the quite decent motion processing witnessed with 2D playback vanishes with 3D Blu-rays, as the picture is suddenly invaded by some pretty excessive judder.
Removing this requires you to use the set's motion smoothing processing, but unfortunately – perhaps because of how hard it's having to work – this tends to cause some quite distracting side effects, such as blurry haloing around moving objects and a flickery sensation over areas of very fast motion. Plus, oddly, using the motion processing increases the likelihood of you being distracted by lip-synch errors.
Many of Toshiba's current TVs have come in for a bit of a pasting where usability is concerned on account of the painfully sluggish nature of their onscreen menu systems. The extra processing power Toshiba seems to have stuck inside the 4K 84L9363, though, greatly reduces this sluggishness.
This makes it easier to focus on the solid layout of the remote control and the straightforward if slightly 'low-res' appearance of the multi-hub onscreen menu system.
The set also guides you through initial setup better than most, with a handy 'flow chart' approach that means you always know exactly whereabouts you are in the installation process.
The provision of a separate app for accessing TV listings remotely is a great user-friendly touch too, and the content-searching facilities on offer show promise even if they're a bit cumbersomely implemented at the moment.
It's impossible to ignore, though, the fact that many big-name brands now ship separate point and click or touchpad remotes alongside their standard ones to aid navigation of smart TV menus. It would be nice to see Toshiba following suit with its next TV generation.
The 84L9363 manages to produce a soundstage that feels big and brash enough to keep the scale of its pictures company – no mean feat when you're talking about pictures 84 inches across. The speakers are powerful and open enough to go loud and proud, and there's even a decent amount of bass to be heard. Actually sometimes the set tries a bit too hard with bass, resulting in some cabinet 'phutting' and not leaving much room for treble detailing to manoeuvre. But overall the basic quality of the sound impresses.
As mentioned previously, strangely the 84L9363 does suffer rather regularly with a loss of synchronisation between the sound and picture tracks, resulting in a rather jarring situation where people's lips don't move in time with the words they're saying.
Here lies the true heart of the 84L9363's appeal. By undercutting its nearest 84-inch 4K rival by an astonishing £7,000, Toshiba has made it surprisingly easy to forgive the 84L9363 for its occasional performance foibles. Especially as it delivers its headline 4K images – unless they're very dark - pretty successfully all things considered.