Here's a story that illustrates what happens when you've spent months reading about projectors and waiting to buy:
My son had his 5th birthday party last weekend and one of the presents he received was a Fisher-Price Viewmaster Projector. This is a red and blue plastic toy that projects Viewmaster slide images using what appears to be a flashlight bulb. After he opened it, a big grin spread across my face because, of course..... I now can test my recently received screen samples! That's right, a 37 year old man getting excited about a Fisher-Price toy. After the party, I rush downstairs to the "Theater in Waiting", pop in 4 D cells, shut off the lights, and project my 1st image in "The Theater". Up go the screen samples, I take my position in the prime viewing seat, I turn a critical eye towards the wall, the kids start running around, and my wife stands there and puts on the "I Can't Believe I Married This Idiot" face.
The scary part is that I could actually judge the difference between the samples. Colors and brightness were obviously the best with the High Power (at least within its narrow cone). I fervently searched through the slides looking for darker images to test the grey screens. These did in fact darken the colors and the blacks. Matt white screens were almost indistinguishable from the wall.
My conclusion - if you are considering this projector, I would go with the high power. The boost in brightness really popped the image off the wall. The blacks on this PJ are already pretty good, so I would skip the high contrast screens. Also, the throw ratio on the PJ is extremely long, so be aware of that if you have a small room. Ceiling mounting may also be tough and I don't know how Fisher-Price customer service is in case you have a problem. The good news is that there was no sign of vertical banding or rainbows! :D
Seriously, my wait will soon be over. I'm waiting for the IF 4805 to be released. Then it will be a choice between that and a L500 or Z2. As a final note, my wife, of course, after the look of shock and disgust left her face, turns to me in the darkened theater and says "Will it have to be this dark for the real projector, can't we just get a big screen TV?". Ugh.....