Personally, I think, 'In absentia' is their best work so far. This is because I think that it has the best mixture between rock, prog and metal parts. Deadwing is good, but it's too much metal. Normally that's not their style.
If you want to know how they sounded, when there were hardly any metal ingredients in their music, you should choose 'Lightbulb Sun'. This cd is very atmospheic and has more classic-hard-rock-parts. This album was made at a turning point, because it was the last one with a small label before they were signed by lava/warner. But my favorite is 'in absentia'. But watch out, here and there it also has some typical brit-pop-parts.
Imo Steve Wilson likes to play with styles, so the next cd could be completely different again.
He has also been producer with Fish (Sunsets on Empire) and co-proucer with Marillion (.com and marbles) and now and then plays with his brother, Ray Willson (ex-Genesis, ex-Stiltskin, ex-_cut), on various occasions (including helping out on live-events and on his cds)
Tracks to listen to:
Lightbulb sun:
Lightbulb Sun
Shesmovedon
Russia on ice
In Absentia:
Blackest eyes
Sound of muzak
Strip the soul
The earlier albums (before Stupid dream) were more or less Steve Wilson-solo-projects, in which he played all instruments except the drums (they were realzied with a drum-machine). These works were partly re-recorded with the current band but I don't know exactly, which are concerned. I don't own any of these.