The highest resolution of the VPL-FHZ55 is 1080p (1920x1080). That's over two times the resolution of a WXGA (1280x800) projector, which is the most frequently found resolution. Across all projectors of this age and type the resolution ranges from nHD (640x360) (worst) to DCI 4K (4096 x 2160) (best).
We think you might also be interested in some of the alternative projectors that have a resolution of 1080p (1920x1080) currently available including because of it's better review score, the Benq SH915, the Acer P7505, or the Viewsonic PRO8520HD ($2,998.69).
Projectors with a higher resolution that might also be worth looking at include the Acer P7605 (WUXGA (1920x1200)), the Hitachi CP-WU8440 ($5,648.99) (WUXGA (1920x1200)), or the Epson 1980WU ($1,140.99) (WUXGA (1920x1200)) which is also higher rated.