Robbo, I'm undertaking the ATPL(H) through Bristol and have found them very good. The course covers all the theory whilst the brush-ups prepare you for the exams.
Not being a spring chicken I found the volume of work on the Module 1 brush up hard work and was frequently up till the early hours. However, the effort paid off as I have just had my results and got 8 passes.
I haven't worried too much about flying during my Mod 1 studies, but will start my hour building now so I'm ready to start my CPL once I'm through Mod 2.
I'd have thought 3-4 hours per day will be hard to achieve unless you are truly dedicated. I only achieve those levels and I'm not working as well.
The CD course is great for subjects that have animated diagrams, other than that I find the paper manuals easier on the eye if you're spending a couple of hours reading.
Good luck.