Based on my experience, they refuse to be accountable for any mistakes they make. Project went months and months over deadline and apparently none of it was their fault.
The worst company to deal with EVER. They do not follow designers plans. They tell you that they have a better, cheaper way of doing it... and at the beginning you trust them. But then you get something uglier and equally as expensive for twice the trouble. Their invoicing is a mess. There is also little to no communication. They overcharge. They told us the project would take 2 months. It has been 7 and the work is hideous. There is much more but not enough characters in this comment box.