This really is where the 58L9363DB lets itself down.
A far, far more accomplished TV than the somewhat disappointing Full HD LED TVs delivered in 2013 by Toshiba, the 58L9363DB is nevertheless slightly hamstrung by the same issues that bug the cheaper sets - usability.
For while it's simple to navigate, it's way too slow, which banishes to the sidelines Toshiba's entire Cloud TV platform and its thoroughly decent ideas and choice of apps. A 4K TV without a dual-core processor? Really? It's a mark off the 58L9363DB's final score.
Cloud TV itself is acceptable, though we were put off initially by the need to agree to myriad terms and conditions, and - worse - the need to laboriously manually enter email addresses and passwords to create an account.
It's all a bit 'why would you?' because there are seemingly no benefits to signing-up; a second failed attempt at remembering our password was enough for us to decide not to spend another 15 minutes trying to accomplish such a simple task. The constant, very loud adverts on a loop for Netflix, Deezer and iConcerts were also annoying.
However, it's the multiple button presses to operate very simple functions that really grated; even turning-off the 58L9363DB took three attempts.
Hardly the 58L9363DB's highlight, the sound quality is on the quiet side. Its two 10W speakers deliver audio that's fine for speech-based broadcasts, but really isn't suited to those sparkling 4K pictures.
Do yourself a favour and get the 58L9363DB chummed-up with a serious sound system as quickly as possible.
Already one of the most affordable ways of getting Ultra HD into your life, we'd wager that the 58L9363DB is destined for more price-cuts; how else will the TV industry persuade us to upgrade?
Despite doubtless more discounting on the way, we'd judge the 58L9363DB decent value for now, though the faster-working and far-better-sounding Sony KD-559000A is only £300-or-so more. The crosstalk-stained 3D is also a slight worry, though whether that comes into most people's buying decision is doubtful.