Thanks for all the advice…
i went for a wahoo element bolt in the end. I am very pleased with it. The buttons are much better than the touch screen IMO. I don’t really miss the colour screen either. It was £259 with sensor pack such as cadence, speed, HR strap. This is FRP so you could probably get it cheaper but I was in London so just bought it from a bike shop on the spur of the moment.
love the phone interface, the simplicity, works without bugs, so reliable, excellent battery life, etc.
highly recommended.