I ran a reasonably heavy load through the machine I've been using here in the US last night, consisting of:
- Some everyday dishes/cups/cutlery
- Pots (used to steam vegetables/cook rice)
- Pyrex baking dish, used for oven-cooked, breaded chicken
- Apple-Pie dish from a couple of days ago. Friend quickly rinsed it beforehand
The latter two dishes did not emerge spotless. There was some residue on the apple-pie dish (which our DishDrawer has always removed without pre-rinsing) and still significant soil on the pyrex dish.
I used Pots & Pans, with High Temperature, so a double wash and quadruple rinsing. Detergent for both washes (Finish Gel Pod for Pre, All-in-One Tab for Main).
DishDrawer back home would have washed these large items on its own Heavy cycle with just three fills (Wash at 158º (70ºC) -> Rinse -> Rinse @ 150º (65ºC)). And there wouldn't be anywhere the muck inside the machine or in the filter area afterwards. I could probably have gotten away with the "economy" heavy cycle which drops the temperatures just a tad.
Machine back home has "left a spot" on a dish used for potato bake, that was subsequently reheated 4-5 times. A lot of mildly burnt residue. I posted that imagery here on AW.
The lack of filter in these machines isn't a big deal, provided you are using a rinse agent, and are careful not to block the water (from the arm or tower). I've seen it mentioned that with tower machines the bottom wash arm really does the cleaning. Not so in this machine. Blocked or not the results are always the same.
I think the issue largely stems from too-short-a Pre-Wash and Main-Wash. They only seem to run about 20 minutes, even with high-temperature selected.
Machine at home runs 20 minutes on the shorter cycles, increasing to nearly 50 for the Heavy cycle and its heating.
There is the chance this machine is underfilling, although I haven't heard any change in washing 'sounds' after adding a saucer or two of water.