I liked this show when it first appeared but over the years it has gone downhill and is now not worth watching. I think the reason I liked it at first was because they seemed quite honest and sometimes said they had found nothing at all. They also don't use mediums unlike most other similar shows.
There were a few bits of the early shows that seemed questionable. Grant is clearly a pretty pushy guy and him speaking to other cast members like crap seemed to be something they wanted to highlight for the purposes of drama. I didn't really like that angle. Then there is the whole issue of repetition. They talk to someone. Grant then tells you that he spoke to someone. Then another cast member then sums that up. This is not taking into account all the repeated information you get because of the advert breaks. You also get a sound track over the entire investigation which makes it seem like something is happening.
For me though I started to lose interest after watching their live investigation where a recorded voice growled "You're not supposed to be here!" twice. To anyone impartial that was clearly a recorded voice. Since then every show I've seen has had Brett saying "did you see that?" and of course, we didn't. Off he runs to investigate but alas, despite this happening nearly every episode he's not wearing a headcam or anything so every week golden evidence of the paranormal is lost. You'll just have to take his word for it I suppose.
I think this show started off quite well but turned to pure rubbish. I see it is now officially described as a docu-soap, sounds about right to me.