At times it feels more like a tech demo than an actual game, but it still offers plenty of clean, simple fun.
The gameplay itself is almost obscenely simple. Tilt the SIXAXIS to tilt the tub and move your rubber duck around. Your only goal is to pick up all the ducklings and bring them to the drain, where they'll be flushed and the level will be completed. The longer the chain of ducklings you get, the more time will be taken off your clock, and completing levels faster means earning bronze, silver or golden medals. These can unlock new ducks to use. They don't change the gameplay, but they give you something to play for, and having a red duck with horns is amusing. The tilt control works well enough for people who are willing to invest the time to master it, but there are many times when it can be overly frustrating. You'll often jump when you don't want to, or worse, not jump when you do want to. This is because flicking the SIXAXIS up jolts the tub, and this control can lead to many untimely failures.
Graphically there's nothing to complain about, though it's extremely simple. The water effects look good and all the ducks look cute, and the game runs at a steady frame rate. These are some seriously weird tubs, though. The music is cute and catchy, if not repetitive, and the water effects are good enough. There are hardly any sounds here, though, and that hurts production values a lot. The menus are a lot of trouble to navigate, unfortunately, because tilting the SIXAXIS moves your selection, and the inability to change the sensitivity hurts.
If you're okay with occasional frustration and simplistic gameplay, then Super Rub a Dub is worth its price, but if you're looking for a deep and engaging experience, then you probably weren't planning on getting this game anyway. In the end, tilt controls can get annoying and you can probably play through every tub in a very short time, but if you get used to the controls then there's stuff to come back for, such as better times and medals, as well as new ducks.