Go with Dulux Spring Breeze 1. At ΔE 2.2 from Little Greene's Mister David, it's a very close match — anything under 2.5 reads as the same colour to the eye in normal light. Spring Breeze 1 sits at LRV 58.8, so it's a properly light, sunny yellow that'll bounce plenty of light around a room.
Mister David is a cheerful, slightly retro yellow — think 1950s kitchen, not acid lemon — and Spring Breeze 1 carries that same softness without tipping into anything too sharp.
The other contender is Dulux Lemon Punch (LRV 62.2, ΔE 3.4). It's a touch lighter and a shade more zingy, so if you want a bit more brightness it's worth a look, but at ΔE 3.4 you'll notice it sitting next to genuine Mister David — it's a near-neighbour, not a twin. For a true match, Spring Breeze 1 wins every time.
Now the honest bit: a colour match gets you the colour, not the finish. Little Greene's paints — their Intelligent Matt and Absolute Matt in particular — have a depth and chalkiness that Dulux's standard emulsions don't quite replicate. Yellows are especially unforgiving here because the way light plays across the surface really shows. So if you're matching Mister David because someone in the house loves it but you're buying Dulux for budget or availability, Spring Breeze 1 will get you there on colour. If it's the *look* of the original you're chasing, the Little Greene tin is worth the extra.
Practical advice: yellows shift dramatically between brands and between formulations, so don't trust the screen or even a printed swatch. Get a sample pot of Spring Breeze 1, paint two coats on a bit of lining paper, and move it around the room — north wall, by the window, under the lights at night. Yellow that looks lovely at noon can go a bit municipal under warm bulbs.