I have both the AOI DLP-03 and zen wa100. The AOI is a tad larger with a diameter of around 4.75 inches, the zen comes in at 4". That surprised me, I expected a 4" dome on the AOI. The zen is better built but the AOI is no slouch either. Both eminently serviceable. My subjective feeling is that the AOI is a tad better though both seem to have issues with in/out shots with "open" f-stops. Couldn't decide if it was dome geometry, environmental conditions, image stabilization or focus considerations/camera technique. Tried quite a few combinations and variables without generating an adequate answer. I am contemplating accepting the field of view penalty and using a flat port instead. Both the 14-42 and the 60 seem to give slightly better images (subjectively crisper images) with the flat port, once FOV issues are ignored, for my working conditions (relatively dark freshwater springs) and photo preferences. May pano stitch to generate greater FOV images for landscapes with limited FOV macro lenses to get the wanted results.