@Crimp1982
Agree with @badgerhead . No real bad schools in Horsham, but it is VERY catchment based (primary schools in particular).
W Sussex make it very clear that your assigned catchment really should be in your choices for primary, as it's the most likely destination.
I can really only speak knowledgeably on W Horsham, but Arunside (primary) and Tanbridge House (secondary) are both very good. For Arunside, you really need to be in catchment, though, as it's an increasingly popular choice. Trafalgar (infants only) also have a decent reputation,though I don't know enough about the linked junior school to comment.
Elsewhere, Heron Way is always popular, as is Kingslea. Holbrook and Littlehaven seem to get good reviews. There is also a new Bohunt primary opening in Sept.
We moved (back) here to be closer to a lot of our family, and don't regret it.
There is a lot going on, the air is fresh, lots of opportunities for our 4 year old etc. You're not far from the coast, but also have most things you need. London is an hour away, and Brighton isn't far either.
It can be a bit of a culture shock at first for those who have become used to London living (things like shops in the town centre aren't open late, and some are closed on Sundays; and a car is def needed to get to some places) but people are friendly, and there is always something happening locally (either Horsham or the surrounding areas). The area has definitely become more diverse in the past decade (a definite positive) and the has been a conscious effort to ensure the town centre remains vibrant (lots of new eateries and developments like Piries place).
The commute is a bit of a pain, though, if it's regular, and is expensive.