Mixer shower flow rates: Advice please

[rsmackenzie]

We're in the process of choosing a mixer shower to go over a new bath. We were interested in the following Bristan valve:
ARTISAN THERMOSTATIC RECESSED SHOWER VALVE WITH INTEGRAL DIVERTER
The plan was to have one outlet for a shower kit and the other for the bath filler (via the waste) thus removing the need for bath taps.

However, when we look at the technical data for this valve it has the following table for flow rates:
FlowRates (litres per minute, open outlet)
Pressure0.5bar 1bar 2bar 3bar
Outlet 1 6.72 9.76 13.89 17.01
Outlet 2 8.96 13.19 19.04 23.32

This looks low compared to other shower mixers. Is this too low for a decent shower (we're not expecting power shower but certainly better than the electric) or indeed for filling a bath?

We are running off a combi boiler and currently get about 12-13 litres per minute off our bath taps (running at shower temperature as measured with buckets!).

Any advice would be great as we're really not sure how to proceed.
Thanks.

 

[plumbnuts]

The normal shower delivery should be around 13 l/min so looking at your figures, it looks ok. Take a look at the Aqualisa digital Quartz combined bath filler/shower. If you can afford this product, it is money well spent and comes with a 5 year guarantee.

 

[rsmackenzie]

Thanks for that. I think that Aqualisa is out of our price bracket unfortunately. But thanks for the information.

The other thing I'm wondering....is there any reason to not go for a combined shower and bath tap set-up? It's like there are 3 options:
1. Separate mixer shower and bath taps
2. Mixer bath taps with a shower attached
3. Diverter valve feeding bath taps and a shower

Will the flow be better with one of these? There is quite a big difference between 2 and 3 (2 being cheaper) but I'm not sure why.