For the flex vs fixed wing decision go with your heart not your head, at Chatteris we now only have a part time flex-wing instructor as the C-42 has been so popular for training (the lure of the heater helps.)
Converting from one to the other is no big deal but will take a few hours of training. Don't chose flex just to save money as the best way to save is to share an aircraft as part of a group, and groups are more common around fixed wing aircraft.
Have fun
