I believe in QLD whats changed is you will require CPEng to apply for RPEQ. So technically you still cant sign off drawings with CPEng, you will still need RPEQ.
RPEQ from what I understand is experience based unlike CPEng which you can just get within 3yrs after graduation with proper guidance/documentation (or thats what a lot of "graduate program" offer). I just find it stupid to pay like 600bucks a year for the freaking membership (CPEng) if you have no use for it. Most companies which require you to have CPEng will pay for it, if thats the case maybe you should considering applying for it.
Like any profession, having such accreditation will definately help in a way. Look at accountants, once they get their CPA, their wage goes up by a fair bit. I'm not saying its a guarantee increment but having accreditation will only do you good IF you need them. Same thing with higher qualifications, a fresh master grad will get the same pay as a fresh degree grad, its all experience depend (for most people anyway, not talking about the deans etc).