Medium-sized 4K monitors are finally becoming a bit more affordable, dipping below £300 (around $400, AU$520), a price point that makes them competitive, between 25-inches and 30-inches, with ultra-wide 21:9 monitors.The AOC U2879VF is the UK's cheapest 4K 28-inch monitor at the time of writing with a price of less than £270 (around $360, AU$470) at online retailers Box and CCL.At that price and given our past experience with first-generation 4K monitors of that size, we'd expect a few corners to be cut to bring the price down.The only real let-down is the fact that AOC opted for a TN panel rather than an IPS one, but that's understandable given the target price.Can it be inferred then that the overall performance will be subpar? Absolutely not. In fact, quite the opposite ? AOC is the first vendor we know of that has shipped a 'colour uniformity data sheet' with a sub-£300/entry-level monitor.