Hi Lara,
I'd say it's a reasonable area.
It's well established and as such, mature so residents are primarily well settled families.
There would not be massive potential for building new apartment blocks etc as the location has limited green space these days. That said, many of the houses there probably appear a little dated, as would have been built in the early to mid 1900s I'd think.
It has good public transport links (Howth Rd & Malahide Rd both have bus corridors, Killester Dart station easily accessable etc).
Local schools include: St Pauls, Mount Temple & Killester, Holly Faith to name but a few.
From what I hear, it's fairly quiet although like everywhere, it has its "hot spots" from time to time.