I guess though that the Sten and the Scurion will always appeal to different markets.
The Sten is small and lightweight but whilst the lamp itself is waterproof (25 feet) the batteries and connectors are not, they're quite happy getting wet and being submerged (sumps and so forth) but they're not suited to prolonged immersion or great depths. So it's not a diving lamp.
Whereas the Scurion is definitely brighter and both the lamp and battery are watertight (as long as you don't damage the battery holder) but it's at the expense of size, weight and complexity.
I like the Scurion, it's a fine peice of engineering (and let's face it, ES simply import Stens, Martin sat down and designed and built the Scurion) but it also has some drawbacks.
When it is available the Rebel 100 (over the current Rebel 70) grade Sten should further close the light level gap, but there is of course the (bonkers bright and equally bonkers expensive) P7 Scurion available.
One thing to note about Stens, is that with every sucessive release of the circuit board they have become a little brighter and a little more efficient. The latest Rebels only come with the latest circuit board and with the new Carclo optics so the improvements are more than just the emitter.
my orders are to sit here and watch the world go by