It's not so much where you live as which Region you select to race in, it's down to the individual, some drivers do elect to race in Regions outside of where they live for a variety of reasons, not just mileage!
Geographically Brighton is probably closest to the South East Region venues and we have had drivers from that area compete in the SE Region in previous years. Though as mentioned in earlier replies there would be some mileage involved!
That being said, do hope to see you at Regional events this year, everybodies welcome regardless of Formula all you need is BRCA membership, check out here:
http://www.brca.org/?q=content/how/9641