I currently have a mixer shower attached to a Puma combi boiler. We've long
since had a problem as we appear to get cycling of the boiler....

What appreas to happen is that the flow rate is insufficient to keep the
boiler running all the time so it shuts down, the shower goes cold, boiler
cuts in gets hot again, cuts out, goes cold etc. This is not so bad during
the winter months as the water entering the house is colder therefore
requres the boiler to be on more to heat it etc. However, it gets worse in
th summer months. I've tried everything over the years to correct this,
changing boiler settings, pressure balancing valves, changing shower head
and hose to increase flow rate etc.

I'm now about the change the shower (we want to change it anyway). I was
wondering about the best one to pick to remove this problem.

I've been looking at the mira excel which says it is designed for this.
Does anyone have any experiences of this and can point me to the best one to
achieve max flow rate to get over this....?

Thanks