electric showers

I just noticed my electric shower started leaking cold water a couple days ago. It's a constant drip from the bottom-right of the case. I didn't notice any issues with how it operated, though. I opened it up, and there's generally quite a lot of water droplets (condensation?) on the inside...

Hi DYI heroes, Our shower wouldn't stop pumping water this morning. Button got stuck. I switched off the mains and we've just opened the case to find that it's got an enormous amount of black soot inside (it covers all the different internal parts as well). We can fix the on and off mechanism...

Can anyone give an opinion on the best electric shower to get. Not concerned about the cheapest but which gives the best output and service.