Nirun has never been that bad, quite the little community in fact. I looked round a studio once (about 10yrs ago) and it was renting for 3.5k. Small though and too many Thai neighbours.
Many of my friends bought condos back when they were cheaper, but buying anything through the registered company route is very dubious - it's simply a loophole and one that they may decide to close at anytime. Where I used to stay, in the Centre Condo at South Pattaya, a guy I know had bought 55 in all just to rent out. Bumped into him last year and he has sold everyone of them since, so clearly the market for them has crashed with the shear glut of them. Personally I would never buy anything that I couldn't afford to abandon - all visas are issued at the discretion of a senior immigration officer, a double edged sword if you like, because if they don't like the look of your face then you won't be living there much longer!
Jomtien does look a better, quieter example of where to stay though I have considered the Darkside mostly due to a couple of KiT's youtube clips (below). It's an area I've never explored (at all) but some seem to like it and I need to know why!