Quality doesn't seem to be that good....
From other forums, quality depends on original size and finished size..
The more sheets you have the quality improves, until you get to one sheet per pixel.
Mind you, you would print a lot of sheets.
If you make a large (say 2metre wide) poster, you are not going to view it from 2 feet away. 1 MB is the limit so it is not going to be exceptional, but it is quick.
You'd probably be cheaper going to a high street print shop