There are a good few threads that you could search out.
Essentially 7" screen is like the Comand look and with function buttons to flip from say radio to Sat Nav.
8" is the cleaner look and w/o the buttons. you've to return to home screen and choose from there to flip.
Either way be sure it has 4gig ram and octo core.
Built-in Wireless and Wired Apple CarPlay. We have added in a version that has been proven stable and re-engineered to give you the most stable Android solution on the market currently. Connect various external devices to expand functions.
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There are more and with varying rear style. All pretty much plug and play and installed in a short time. The add ons take longer.
Allow for an external mic, I mounted ours into the roof lining behind the sun visor.
I didn't check the links but also be sure it has DSP.
Edit,
I see the 7" has DSP listed,
I can't see the same in the 8" description, and it's in Spain anyway so with possible customs costs it isn't so good.
Maybe you will find one in UK with DSP if that's your preference.