Hi. Just wondering which I will pick for my bathrooms. Mira Honesty is more expensive than Mira Atom . The min flow rate of the atom is 3.4 litre per min whilst the min flow rate of the honesty is 4.5litre per min. 
If there any reason not to pick the Atom. My new air to water system is a 250 litres(ish) tank, so would it be better to get the lower flow rate. Interested on why people would pay substantially more for the honesty than the atom. Interested to hear your views . Thanks 

3.4 lpm sounds like a dribble. I think that will be one of those showers you will be shifting about looking for some water! 

What are the maximum flow rates?

The minimum flow rate doesn't really matter unless you're into really saving water. If the maximum is sufficient then I can't see the reason for buying the Honesty, as I looked at the Atom and it seems fine to me.

Min flow rates may be important for some combi boilers, but for anything else, min flow rates don't make much difference.