The Benq TW529 supports a maximum resolution of 1920 x 1200 (WUXGA). That's over seven times the resolution of a 640 x 480 (VGA) projector, which is the most common resolution supported by new comparable spec projectors.
A 1920 x 1200 (WUXGA) graphics resolution is actually the best supported resolution amongst all 13000:1 contrast ratio multimedia projectors that are a similar age to the TW529.
Amongst comparable types of projector the worst supported resolution is 640 x 480 (VGA).
There are a number of alternative data projectors that support a resolution of 640 x 480 (VGA)|1920 x 1200 (WUXGA) currently available which you might also want to consider including cheaper projectors such as the MS527 (£237.19), the MW529 (£299.25), or the MS527 (£237.19) all from Benq.
If the resolution of this projector is not high enough for you then you might also want to look at the Benq MX528 (£335.86) (640 x 480 (VGA)|1920 x 1200 (WUXGA)).