Thanks Ancient Mariner- that is exactly what I needed to hear. I have ordered the 14.5 Ultima and I'll let you all know how it turns out.

Thanks B Star and yes I recognise it's all a bit obsessive. But its an expensive unit and I just want some reassurance before spending that money that it will…

I am having exactly the same issue with that system.
I'm stumbling around in the dark using formulae from the internet that may or may not be right and I…