Yes bin lottery :-). All the LEDs manufacturers pride themselves on advertising brochures with extremely high product performance that is achieved by a small percentage of total production (and is usually not available for mass purchase). As you can see, these are all quite fresh products (a common feature is the square emission surface). To be honest, I have to admit that I started this project a few months ago and did not follow new products of 3030 class from other manufacturers. Osram GW QSLM31.QM, as I can see, has a lower thermal resistance but is a single 3V diode (in this design you would have to use them twice as many). It also has a statistically lower forward voltage (hence a slight advantage in efficiency at similar currents, e.g. for the 2700K option).