I wasn't really a big fan of their former location (hard to get to from an out of town perspective) -nothing makes you baulk about going to an event or writing group in the city like having to drive two hours and then find expensive parking.
I did visit the Institute Building twice last month for an art exhibition that my wife participated in and
despite it suffering the same issues that plague all old Adelaide buildings (inadequate air conditioning) it is a very grand venue with easy drop off access and some good parking down along the Torrens if you don't mind a short walk.
So if you have been a past member or are curious about getting your writing career started check them out.
They open again on the 9th January so you can have a look around their website till then.