No personal experience with them myself, but just watching their commercials convinced me that they are not something that I want to get involved with. They mention the huge savings on their products, but as a contractor, I sort of have an idea of what those things cost, and the numbers they are using are on the extreme high end to compare the savings to.
Most of it is in custom cabinets built to order by a cabinet maker. If you are buying pre-built cabinets, then you can get the most expensive ones that the box stores for less then the ones they are advertising as being a great deal. In my opinion, the mid priced cabinets are very good at both Home Depot and Lowes. I've also had good results with the lower end cabinets.
When you figure out how much it costs to have custom cabinets built, then to have them finished with either stain or paint, you are in the big money for kitchens. You get a better finish with the box store brands, better hinges and they are always perfectly square. The price can be as much as 4 to five times as much for custom when compared to what I think is a better quality cabinet from the box stores.
Eddie