What you're actually buying here
This is not a toy. The LEGO Icons Star Trek U.S.S. Enterprise (set 10356) is a display model, full stop. It sits alongside things like the Eiffel Tower set or the Titanic in LEGO's adult-oriented Icons line. The build is substantial, reportedly around 2,500 pieces, and the finished model is designed to be put on a shelf and admired. If you have children who want to play with it, this is the wrong set entirely.
At £309.99 with no current discount, you are paying full retail. The 778-degree heat on HotUKDeals reflects enthusiasm for the product itself rather than a particularly sharp price. Worth keeping that distinction in mind.
The honest case for spending this much
Amortised over a few years of display enjoyment, £310 is not outrageous for a centrepiece model. Compare it to a framed art print, a quality piece of memorabilia, or a mid-range figurine, and it starts to look reasonable for a Trek fan with a dedicated shelf. The build experience itself typically runs 10 to 15 hours for a set this size, which is a meaningful chunk of relaxed weekend time.
That said, LEGO sets in this price bracket do carry a known weakness: they gather dust aggressively, and the plastic can yellow over years if exposed to direct sunlight. Neither is unique to this set, but both are worth factoring in.
Who should probably pass
If you are not a Star Trek fan specifically, this is a hard sell. The NCC-1701 silhouette is meaningful to Trekkies and largely irrelevant to everyone else. A general LEGO enthusiast would likely find better value in the Millennium Falcon or similar, which has broader cultural pull and a more dynamic shape to display.
For a committed fan with the shelf space and the patience, it's a serious object. For anyone else, £310 is a lot to spend on nostalgia that isn't yours.