Primrose isn't a patch on SJW. Granted SJW isn't trendy wendy but it's a different league to NW1. If you want to party, SJW isn't going to rock your life but if you want a first class living environment then it's hard to beat.

Hampstead is nice but the Northern Line is useless and having spent many years using it (and now use the Jubilee line) could never go back. Hampstead really is quite a lot further out too.

Parts of Maida Vale very nice depending on where you commute to - Little Venice etc can be more fun.