I say yes contact them. I've contacted them at least 30 times since I started this journey over a year ago. I've yet to get someone who was in any way un-helpful. Even when they couldn't offer an answer they did their best to try and find the answer. Relying solely on this and other groups is not the best idea. It's your life, therefore you need to get as much information as possible therefore you should be getting as much info as possible. That includes groups like this and DIMIA. I wrote to this group the other day and had a couple responders who were unable to answer my enquiries. So I phoned DIMIA and got answers. I think it's important to use this group and DIMIA cause you get both sides of the story for an answer.
Remember ignorance of your visa obligations are no excuse and you could find yourself being kicked out if you get the wrong advise - so use everything you can so you can be well informed. Somewhere on DIMIA's site I found a page that listed the numbers of people kicked out of Australia for not living up to their visa obligations and there have been a lot of people kicked out.
So swallow your fear - this is not communist russia the kgb won't come calling just cause you want to make some enquiries. You don't have to say who you are to ask questions; no one has ever asked my name when I've phoned.