Hi Jarv - welcome to PPRuNe!
I'm not quite sure what you mean about the "magic 150 for entry to most Modular courses". If we're talking about ground-school, the only requirement is to have a PPL. So go for it!
You've got a good idea of what's involved in the exams by now. There are basically two ways of studying in the modular world - residential, or distance-learning.
Residential full-time courses would, I imagine, work in a similar way to the ground-school training on your integrated course. You turn up for class each day, study with other students, have the support of your instructors and fellow students being around you.
Distance learning is generally the harder option. You get a set of notes to take home and study in your own time. Before the exams, you get to spend some time (2 weeks, usually) at the school doing a "brush-up", which basically reminds you of all the stuff you've forgotten from the start of the course, and then overloads you with enough feedback and practice exams that you're ready for the real thing.
Generally, I would suggest the residential course (unless either money or time precludes it, which doesn't seem to be the case for you). But in your case, since you've already had a go at classroom training, and haven't managed to achieve what you want to achieve, maybe the distance learning would suit you better? Only you can decide that - it seems that youv'e got a good graps on your own strengths and weaknesses, so think it through carefully and decide which to go for.
Once you've made your mind up (or even before you've made your mind up) have a look at the
list of approved schools and contact all of them that offer the type of course you want. (If you haven't made up your mind yet, then contact a selection of residential and distance learning schools.) Tell them your situation, ask what they recommend and what support they'd be able to provide you, and go with whichever one gives you the best feeling that they're going to take care of your specific needs.
As for the hours requirements - there are requirements that you have to meet before you can start the CPL flying training, but let's get the exams out of the way first!
Good luck - and let us know how it goes!
FFF
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