Ah, I made another reply in your other thread but maybe here is best place.
If you are focussed on state schools then you need to weigh up how academic your DD is, and whether you care about league table stylee results or other factors.
The 'best' state school available to people in Exeter, based on academic criteria, is colyton grammar. Insanely competitive to get in, though. If your DD isn't very academic then it might not be the best place for her.
The 'best' state school in Exeter is St Peters. You basically have to be a regular church goer to get in, though. It's also a bit of a schlep from St Davids Hill. It gets good, but not great results. Everyone I know who goes there loves it, and I have known some kids get superb, outstanding results from there. It is a true comprehensive though, since it has no catchment area so it is impossible to buy yourself in through being able to afford a big house. If you are not regular church goers though, it is unlikely your DD would get a place (not impossible, mind. But a risk).
I thnk, but I'm not certain, that St Davids hill primary feeds into St James. This school has a poor reputation and doesn't do well in league tables but it may offer other things. I don't know anything about it apart from its reputation, though.
Isca has a mixed reputation but I have known kids who have gone there and done very well. I understand from our next door neighbours, whose two kids have gone/are there, that there is a pretty brutal streaming regime which means the academic hard working kids are able to get on with it. This school has an arts and media focus. The facilities - as with all the Exeter state schools - are fabulous. They have all been rebuilt over the last 5 years.
Living in St Davids you won't have much chance of getting DD into West Exe school since this doesn't have enough places for the kids living that side of the river let alone anyone else! Other option might be QE in Crediton (reasonable rep, USP is that it has a 6th form).