General question: Combi versus back boilers/immersion

[Londoner]

Are combi boilers generally only suitable for flats or smaller houses? I have lived in a number of flats and I like the convenience and efficiency of combi boilers, but looking at houses recently most seem to use a combination of a back boiler and immersion tank (a system I'm unfamiliar with).

Would you say that as a rule changing to a combi is always better, or is the back boiler system better for larger homes?

 

[JPC]

some folk always like a combi....
there are some cons thou...
no reserve water if water is turned off
water pressure suffers if more than one tap being used. (hence in bigger houses with kids u might want a diff system to a combi)
is ur water pressure good ?
can take an age to fill a bath.
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