water leaking? Ariston quality like bad nowadays. give other brands a try?
nothing wrong to change to instant ones.. but i read they are more energy consuming.
the other is gas water heater... but quite a bit of work required like laying gas pipes etc...
Instant heaters have higher power wattage because they are required to heat up the water instantly. But in terms of energy usage, instant water heater will actually save electricity because you only heat up whatever water you need while storage heater stores up heated water and some of this heat is lost and energy is wasted.
I use a storage heater in my previous house. It was good because it supplied heated water to all the taps and toilets etc. But later on I only use one toilet and I don't need heated water for all my taps unlike in cold countries. As I did not leave the heater on all the time, when I needed hot water to bathe I would have to wait quite long for it to heat up. Then my storage heater started leaking so I converted it to an instant water heater and I can bathe instantly especially when I am rushing to work in the morning and none of the heat is lost.
I usually buy 707 as I can see the quality of the parts but recently my wife bought a Panasonic with ELCB at half the 707 price. It is plasticky inside but so far it is also working ok.
I would not use gas as I think they are very dangerous. Your house may explode if the gas is not properly ignited. It is far easier to ensure safety if the electrical is well installed.