I had purchased a number of purple ink samples with the intentions of trying to find a vibrant purple ink for special usage. It needed to be more on the blue end of the purple spectrum, rather than the red/pink end. Diamine Imperial Purple was certainly a winner, in those regards.
This review was scanned at 600dpi on an HP Officejet 6500 E710n-z.
Note: Because these scans are done with a light emitting printer, actual colors will, more likely than not, be slightly darker than they may appear, here. The colors shown, here, are probably a bit more reminiscent of what the ink would be like under a bright light or if it were held up and viewed with a light behind it.