I've never used the Samaritans but I have used my university's Nightline. The first time I used it I spoke on the phone to someones, then I discovered they had a text service and from them on have just texted them. I know it's not the Samaritans but it's somewhat similar and like people have said, some people are more 'useful' than others, but on the whole I only have positive things to say. It's been there when I've needed it the most.