Hilly Fields is nice, but whatever you do steer clear of Upper Brockley Road near Lewisham Way. The other end is perfectly fine.

I lived there for 8 years and it was a nightmare.

I prefer Sydenham (and Forest Hill) to Brockley. When I was looking 4 years ago I found Forest Hill both cheaper and better value than Brockley. If you get the train from New Cross you will struggle to get on the train in the morning, plus you have to walk through New Cross. Brockley isn't too bad to get on the train.

Best thing is to have a good look around and judge for yourself. My experience in Brockley is tainted by some selfish idiots who think either turning a blind eye to whats going on or doing whatever you please irrespective of how it affects others is acceptable.

Brockley Central is a great site though. You will get lots of info there and Brockley Nick is a nice guy.