The Viewsonic PJD5150 has a maximum resolution of SVGA (800x600). That's 53% less resolution than a WXGA (1280x800) multimedia projector, which is the most common resolution.
This data projector's resolution (SVGA (800x600)) is in fact the worst resolution amongst all multimedia projectors that have been on the market for around the same time as the PJD5150.
Amongst similar types of data projector the best resolution is 1080p (1920x1080).
We compared all the other projectors that have a resolution of SVGA (800x600) to this multimedia projector and we think the S310e (£159.99), and the S310 (£482.63) both from Optoma which is cheaper; or the Infocus IN112 (£199.98) which has a better Rating are also worth considering.
Projectors with a higher resolution that might be worth considering include the Infocus IN116 (£329.99) (WXGA (1280x800 and cheaper) and cheaper).