Be careful with Proteus V4. While looking good (sometimes extraordinary) on the first sight this model does sometimes introduce heavy artifacts in darker areas, at least with lower quality sources.
After the initial hype had gone I’m still constantly preferring Iris LQ with optimized settings to Proteus V4.
In general there’s little difference between both (with a slight edge towards Iris LQ) but what really kills Proteus V4 is this sporadic artifacting.
EDIT (added examples):
Proteus V4 vs. IrisLQ (with manual settings):
This is what it mostly looks like with my sources. Little difference but 'I still would give IrisLQ a slight edge. Microphone is where it’s the most obvious, also teeth.
But then with ProteusV4 you also randomly get such:
Look at the crowd
