petediscrete
First, thank you for trying to help. However, as you can guess I'm not going to opt for a sat>IP tuner and I really don't care about 4KUHD (at 72 I've seen enough overhyping, but to be fair moving from SD to HD in the US was a big deal, not so much in the UK, and please do not get me started on about PC screens that need to be at 200% to have readable text).
I'll have a look at the Rock machines and see if I can find any performance comparison.
heitbaum
Thanks for that - it explains the very limited command set table 
At least I now have some idea where I'm going and the fact that I'll need to add £40 to my budget for the Pulse8 USB adapter
Out of interest is there any usable documentation regarding CEC out there - if there is I was searching for the wrong terms.