I was there for weeks and weeks over 2015/2016 (booked a three month stay) and it's clean, cheap (I think $200 a month CAD), the staff are OK (by Thai standards) and the building in and out is aesthetically pleasing.
BUT, the noise off of Huay Kaew road is past belief. All night young idiots roar up and down on motorbikes minus mufflers. Also, the wifi is simply awful. You gotta stand by your door to get a signal. Not just me, but everyone. I'm fed up anyway with Chiang Mai what with the explosion in traffic over the last couple of years, but if I weren't I'd go elsewhere than the Dome. A plus is Noi's cafe in the lobby.More