Mike, I wish I could, but there's more to it. I'll help you as much as I can with my very limited knowledge base about these things, but I encourage you to be patient. I would say this even if you lived in the US, but the fact that you live so far makes me feel even stronger about that.
Ok, let's see. The BW offers higher gain, but an angular reflective with higher gain may suffer more hotspotting, or less uniformity. But, since Carada seems to have such a good rep, methinks that the downside is not bad. OTOH, are you able to play with projector height? You most likely will get this bit of extra gain when more on-axis, and that paying for the cost and any possible hotspotting would not be worth it if at quite the offaxis angle. I am sort of pulling this out of my butt, or synthesizing among the bits I've learned, but it's something to look into.
So, I guess if you think you don't really care at all for extra brightness, then go with the standard screen. I encourage you to listen to rmk's advice and get as many samples as you can.
Yes and no. The viewing angle might be the same, but the immersion is not exactly. After all, if I put a cell phone 3 inches from my eyes, it's not the same experience, as greatly exaggerated as that is. I once ran into this
post, which I thought was rather interesting.
But, ok, the sizes are going to be close enough, that I would just position for best acoustics, and perhaps go from there. If the acoustics are a moot point between the different spots, then yeah, I vote bigger!
I'm using this.
http://www.da-lite.com/products/product.php?cID=9&pID=231
The extra coupled hundred dollars is worth it for the C model over the B for the better roller mechanism, but when it comes down to it, I forget how limited the B can be in size anyways (not very big IIRC). I added CSR for a bit which is supposed to help in rolling the screen up and down. If you never will roll it, you don't need it. I also custom ordered the mechanism in black for about $50 more. The image is fantastic, phenomenal, but having the projector closer to the axis of the eyes is imperative. Doesn't have to sit on your head, but closer is key. I'm talking about High Power.