what are the best immigration specialists to use?

Hi there,

I'm just wondering if anyone can recommend a good immigration specialist? I've been doing a lot of research and contacting so many that I'm starting to feel overwhelmed. A few have definitely seemed sketchy but there are two who have been quite helpful and I'm just wondering if anyone has anything good to say about either? One is medivisas and the other is Commonwealth immigration consultants.

Basically, I'm from Canada and have been here on a working holiday visa for almost 2 years, living with my partner and we are looking to switch to an unmarried partner visa.

If anyone can give me any advise that would be great!