Hi!
I'm homeschooled and do all my iGCSEs myself. This means I can choose what exam board I do, and I would choose CIE over any other board. I took a class for Biology and they were doing Edexcel, but I wouldn't choose it again. Nor AQA, I found their mark schemes very difficult to understand, for Psychology anyways. So I think you're making a great choice switching to a CIE school!
Some students find the CIE exams harder, but I don't think they're any more difficult than other boards. There is a distinct lack of resources online and in books for the CIE exams, but if you look hard enough then you'll find some. If you would like some resources, I'd be happy to share some of my favourites. I'm new to the Student Room, but I think if you reply to this conversation, I should be able to see it. Just let me know what subjects you're doing. The CIE subjects I've done are Geography, Environmental Management, Physics, and I'm currently doing Chemistry, Maths and First Language English.
Good luck with everything!