1) The shower head tends to turn and twist around without notice and usually goes everywhere but straight ahead (as seen in pic). Or you can take it off the hook...
2) Noticed that there is no shower curtain? This is not always so, but I've seen this (what I consider indispensable accessory) missing more than once. Differently from India, bathrooms here are not wet. So what is the fun of taking a shower if you have to take care the entire time not to flood the bathroom?
3) Why are they always so low? Norwegians are definitely tall (I'm about average here) and the support for the shower head usually is only as tall as my shoulder (one more reason to use it as handheld).
In my opinion these points make them barely better than the bucket-and-pitcher combo.
Not handheld: check!
Height above head: check!
So what is the issue here? Water is heated as it goes through coil in the shower head. This means that the shower only has so much "capacity", meaning that the more water comes out the less it heats. In the Summer this is not a problem since the country is so warm. But in the Winter this means ending up taking a shower of droplets. And in case the fuse blows... bad luck, cold water for the rest of the shower!
Ah... bliss! Shower curtain in place, right height, hot water and, get this: the more you open it the MORE hot water comes out! Add to this that most houses have good water pressure and that's it, your daily troubles are down the drain! I must admit that when I first moved to the US from Brazil, in January in Virginia, I took a cold shower for 2 days because I did not figure out that you have to open the shower more (not less) to have hot water come out. But after this small quirk was fixed I was hooked! Oh, how I miss the US showers!
Definitely not efficient though...