Todd, I don't have a High Power screen, just a 65" diagonal matte white screen for now. I did see a 150" diagonal high power screen (projecting only about 110", or maybe it was 120"? The throw didn't permit a larger image at the time) with a table mounted Benq 8700, with only 20 hours of lamp time. It looked nice and punchy. With a few tweaks to brightness the black levels looked quite good for most material we saw.
Keep in mind that I'm using Takisot's (try a search, he has some nice tweaks) DLP menu and user menu tweaks. The DLP brightness was dropped to -4 from the default of 0, which is a LOT of brightness lost. DLP brightness is basically a very course brightness adjustment - when combined with user brightness it seems to give you more brightness range.
I'm pretty sure my Benq is only outputting 350 lumens now! User contrast is at 18 too.
Todd, I suggest you press Memory 3 on your remote - it lowers the brightness quite a bit, and will give you an idea of how bright my image is. Assuming you didn't reprogram 3 that is.
I like Tryg's reviews, because since everyone's ideas of what a screen should do is subjective, he at least tries to compare them with each other so we can use our own judgement based on his (more) objective comparisons. And he does it without throwing measurements around making it easy for laymen such as us from getting swamped in the details.
I liked the High Power when I saw it. Surprisingly, the elevated black level didn't bother me as much as I thought it would...it really does depend on the video material used. Movies such as Fellowship of the Ring, even in dark scenes, looked really good because of the way the film was shot...dark backgrounds but always with a bright light source or reflection in the foreground (ie. torches, well-lite character's faces, shiny swords, etc.). However, if the movie is very dark with low light sources, the overall contrast is extremely low, and will not look nearly as good - and you may perceive elevated black levels as a result. At least with a high-gain screen, you have a better chance of perceiving subtle shadow detail.