I think it depends what exit point you want to shoot for too as well as the overall feel of the school.
I was originally against the 7/8 plus believing that it would be too much, but… that’s actually what we ended up doing as I realized it would be slightly easier to prep for an exam when they’re younger and not have to worry about the 11/13 plus with nothing to fall back on.
With that being said Wetherby would probably be the best for leaving at the 7/8 plus as that’s what they focus on. I have a friend with two sons there and she loves it, says it’s not too pressured as they slowly lead up to the exam. Fall back option with the prep in Marylebone has good results too and exit options at 11 and 13.
Eaton House Belgravia has been doing very well recently honestly, I think it’s becoming just as popular as it used to be after a little stint pre-pandemic where class size dwindled slightly. Great for academics and goes to 11.
Garden House is more relaxed, and I’ve heard about them wanting to expand to 13+ and not prep for 7/8 anymore, but that expansion has not take place yet so I wouldn’t bet on a 13 exit. I think some parents here do tutor, but overall they have happy kids. Many kids come from the local Chelsea area.
Falkner House boys is also great, lots of boys there have siblings at the girls school, which has similar academics. Depends how far you want to go as this is probably the furthest west on this list. They prep for 7/8 and also have an exit at 11 for boys who aren’t ready yet.