There had been some recent discussion whether the print quality of an ET-8550 would vary visibly vs. printers like a p800 or other printers with light inks. A visual comparison is possible but it is quite difficult to describe and rate possible differences.
I did this - I printed a patch sheet with 283 colors with the ET-8550 - ultraglossy quality best and with an L1800 - 6 color dye inks incl. LM and LC - ultraglossy quality high.
I selected a green patch from both prints - the patch size is about 7,5 x 8,5 mm and scanned them with resolution 2400 dpi.
A small crop from the ET-8850 scan looks like this
This is a small crop of the L1800 print scan - probably 2mm wide as orginally printed
There is some variance visible - some luminance and chroma variations.
I'm loading these patch scans into the Monaco gamut viewer and display them as pixel clouds
The center of the pixel clouds are locaed at slightly different colors - green in the +b -a section of the Lab color space - I selected slightly different greens for demonstration so that the pixels don't completely overlap.
More important are the size and the shape of the pixel clouds - yellow for the L1800 print and green for the ET-8550 print.
Please be aware that the eye is more sensitive to luminance variations than to chroma variations. You could do more statistical analysis on these color patches - e.g. the size of the areas with color variations, or a spatial Fourier analysis could reveal repetitive patterns - e.g. banding or from the dithering algorithm, but I don't have such software on my computer anymore.
I printed complete profiling patch sheets, this could allow me to do a similar analysis of other colors but I won't since I don't have an XP-15000 to compare with.