I've recently completed the CBIR ground exams and am waiting for March / April to complete the flying. For the ground school I went with Caledonian (captonline.com) , mainly on the basis that they were cheapest and I couldn't really see any benefit in the more expensive options. The notes were delivered in PDF and book form and were OK but for some topics I did find myself hunting around for other sources to help me understand. Caledonian also maximise the amount of time you do via Skype for the classroom stuff so less time having to travel to far corners of the country. But the thing I couldn't have passed without is the question bank - I used Aviation Exam. A lot of the questions seem to be worded in a way to deliberately catch you out and it's only by doing the question bank that I gained the confidence to spot the traps.
I know the syllabus is simpler than the old IR syllabus but it still seems to contain a bunch of stuff that will never be useful (distance of the Galileo satellite system from the earth anyone....?) It's also a bit weird that (to use Flight Planning and Monitoring as an example) that IFR flight planning, fuel planning topics etc are in the CBIR syllabus but flight monitoring / in flight re-planning isn't (but is in the ATPL syllabus). I suppose my point is that there seems to be a lot of useless stuff that is included in the syllabus and then some useful stuff that isn't!
I (perhaps foolishly) decided to do all 7 exams in one week and was relatively happy to pass 5 out of 7 first go (pass mark is 75%)
I got 90-100 in Air Law, Human Performance, Instrumentation and IFR comms and found that I had decent time in those exams to go back over my answers. IFR comms was a bit ridiculous in that it took about 3 hours to get to the exam centre from home and back and 10 minutes to do the exam. I scraped a pass in Radio Navigation and did find that topic a bit more challenging.
I failed Met with 68 I think because it's the topic with the most content and I simply hadn't spent enough time on it. I passed that 2nd go with a 94.
The one I found hardest was Flight Planning and Monitoring and I failed it twice with a 70 and 73. Unlike the other topics this was the one where each question wasn't necessarily hard but you have to do about 30 questions in 40 minutes many of which involve having to wrestle with maps or do multi-part fuel / nav calculations so I found myself working at speed, taking the first answer I got to and then not having any time to go back and double check my answers. I'm pretty certain I'd have passed first time if I'd had more time so the key to this topic is being able to do it really fast.
I did the exams at CATS in Luton which was fine. There's a cafe in the reception area downstairs and tables where you can sit and cram if you're waiting for your next exam.
I'm now thinking that maybe I should have done the CPLs in case I want to instruct in the future but never mind.
Hope that helps - let me know if you need anything else.