Congrats to your DS, no-ball!!
Just a quick reaction to your post:
If you live in Solihull, it seems that distance is roughly equally the same, isn’t it?
Warwick is not at the same level in the league tables as KES... It is less selective academically... You could also check the number of offers from Oxbridge for these two schools as a mean of comparison (if available?). So my immediate reaction would be to say KES.
However, I have no experience of these two schools.
Like you, I visited them during open days.
Well, if WW5 is about to start in your home, I imagine it is because you DS prefers Warwick while you prefer KES... Am I right? Truly, Warwick school IS a beautiful school.
You have then to think about which route you prefer: A levels or IB (the same old question!!
Good luck with all these weighing of pros and cons... Ah, the hard job of being parents...
I hope parents who have their children in these two schools will be able to give you proper feedback...