I own an LG model. I haven't found it as useful as I thought I would.
The biggest problem I face is in loading odd sized vessels used in Indian cooking. Hard to put a pressure cooker or a kadai in. If you use a lot of china (or utensils easy to stack), it might be useful.
As already mentioned, if you do cooking which makes food stuff stick to the vessels, you will have to scrub the food off before you put it in.
Dishwasher's action is more like rinsing. If you need to scrub your vessels everyday, you may not find it very useful.
EDIT: On the brighter side, the stuff that I can fit in comes out really clean.