I have used their inks in my small refilling business for 4 years and have had very few problems. I have also sold their compatibles, and while the Canon compatibles have always worked well and are trouble-free, I can't recommend the Brother compatibles, nor the newer Epson compatibles, which have about a 15-20% rate of return.
They appear to be the only ones selling chipped Canon PGI-5s and cli-8s, and my customers are really thrilled with these since they maintain the ink levels. So, it's a mixed bag, but all in all, they are a good company to work with.
I've been using them for a number of years, their ink is of high quality, and I am very pleased with them. I don't sell their compatibles, so I can't give an opinion on those.