We have had a full size "roll away" dishwasher from Sears, ours is a Kenmore, since 2002, it has a top and bottom sprayer. I think it was about $500, and we moved with it, too. We did buy the extended service/maintenence plan for it and for our Washer, Dryer, and Fridge (all bought at the same time) - we had to use the service plan ALOT on the washer and dryer, so it was worth the extra cost, but the firdge we left at the other house after 2 years, and the Dishwasher has never had a problem. We were getting a film on the dishes for a while,and I had the tech come and do the yearly "check-up" covered in the maintenance contract, he told us to use powdered detergent, (not liquid, packets, or pellets) and to only fill the detergent spot about 1/2 way for a full load - not a problem since.
You so have to be careful with the roll aways that you rinse off any big food particles, since they don't have a "grinder" in the drain system, and it all has to drain through a hose into the sink. Our dishes have always gotten clean, but it is noisy, and even on the light wash or water miser cycle, it runs for a whole hour. All that said, I am still so glad we have it, both our kitchens had no built in dishwasher, and I didn't want to lose any cabinets either, but especially now, with baby bottles, I am so glad to have a dishwasher of some kind! It has never leaked, in 7+ years. My mom had one of th elittler ones, and it did leak once - that was becasue my Dad was trying to help by doing the dishes and put hand-washing dish soap (you know like Dawn) in the dishwasher....that stuff foams up too muchand it somehow breaks the "seal" around the door and then they will leak....I don't think it was permanent, though, I think after that load was done and rinsed out, the dishwasher worked perfectly well - just something to keep in mind - don't get any sink dish soap or hand soap in the dishwasher by mistake!
jessie