Electric v mixer shower: R all combi boilers created equal?

Complete newbie to the DIYnot forum and in need of some expert advice!

Recently moved to a house with a Valiant combi boiler that is a around 2-5 years old. Replacing an old electric shower and have a problem with deciding to go with electric again or a thermostatic mixer shower.

Ideally I'd like a thermo mixer as I'm not sure that electric a)has the pressure and b)not too expensive in the long run.

I've asked around and of course everyone seems to have a different opinion! Someone recently told me that the power of a mixer shower is affected by the flow rate from the combi boiler and that I should go for an electric if the flow rate is low.

ultimatley I want to know if the electric is better (pressure, heat, cost wise) than a mixer if the flow rate is low OR is it still better to have a mixer regardless Please HELP, I'm going round in circles!!!

you'll get a better shower from a combi, as long as you have reasonable mains, which you'd need to measure to judge.
Other hot taps would affect showering drastically though.
Gas is cheaper at the mo than electric, so costs would be about the same.

Can't use a power shower on a combi. Which Vaillant is it? I agree it is best to fit a thermostatic shower rather than an electric one usually.

Electric showers are very useful when the combi packs up....

(Lights blue touch paper and stands well back)