Is adding a Megaflow to a combiboiler a good idea?

Muumi

Hi,

I was wondering if anyone could give me some advice on a boiler issue. I'm in the process of having a loft convertion done and want a really good shower up stairs (Maybe one of those rain curtain ones) as I'll also be putting in a small Sauna up their as well. I have a perfectly good Combi boiler (which I'm guessing is a few years old) but despite the fact the 1st floor bathroom works fine I'm worried (and all builders have played this up) that the loft shower may be a drizzle rather than a rain curtain shower. What has been sugested is I connect my existing Combi boiler up to a MegaFlow and use the Megaflow to supply the water for the whole house. Does the seem resonable or are they trying to pull a fast one? Also if I understand it correctly, the megaflow is connected to the radiator circuit of the combi boiler and heats the water through an inner coil. Does this mean that to heat the Megafolw water my radiators have to be on also (Clearly undesirably in this sort of whether!).

The figures quoted is about £2K for the boiler + work. If the above does seem resonable does the price also seem OK?

Thanks
Muumi