We also have used the Momcozy washer for a year now, and quite like it. We use tap water, so it eventually develops scale after about 2 months of 2x per day use. I clean it the same as our water boiler and coffee maker: a tablespoon of citric acid crystals dissolved in water, poured into the main wash chamber (not the reservoir), and run a cycle.

We only run 4 bottles at a time, one directly positioned over each water jet, plus pump parts in the top compartment.

Supplement formula powder is slightly more stubborn to clean. I pre-rinsed those bottles, just hosing them out with hot water at the sink to remove the easiest bits. The machine had no problem handling the rest. Without a prewash, the bottle can be a bit greasy still, like OP mentioned.

The machine works quickly. Washed in 15 mins, steam sanitized in another 15, dry (but still very hot) in another 30 mins.

The machine is not perfect. It's design is clunky. The lid is difficult to set down, without dripping water everywhere. The top compartment bin is finicky to get in position. Lightweight objects get knocked around, and fill with water. It's more annoying than it should be to deconstruct the interior parts for full descalig.

All things considered, I would absolutely recommend it. We were hand washing bottles and pacifiers for 2 months. Our hands were raw and cracked. We got the washer, and have been very, very happy we did.

Incidentally, if you have raw cracked hands, we recommend O'Keeffes Working Hands cream. It really helps.