The screen will be a roller blind- The projector will be used with a computer to play flight sims and occasional DVD films. At these distances is 1. screendoor and rainbow effect in DLP evident/accentuated/less so?? 2. SVGA more acceptable or less - I would really like XGA. Is the latter a must? Lastly where in Hants / Dorset can I get demos- Not as easy as you think!!