what thermostat/programmer should i get?

I have a brand new system, i have worcester bosch solatr panels going into an unvented tank and a w/b 30 cdi system boiler. I have looked at all the W/B thermostats and programmers and they say i need to fit a diverter valve if i am using their stuff but my boiler cant have a diverter valve fitted. they suggested something from honeywell but I cant get a straight answer about whether that needs a diverter valve as well. I am totally frustrated and confused help?