Blimey this thread has got big..
First off sternone, well done on your progress so far you should be proud of what you have achieved..

I'm about 50 days into my lab time, so far I've watched about 20% of the videos for the course and only used the PDF as reference material.
I think I've rooted just over 30 boxes now. This isn't to brag, I'm not a pentester or security expert this is the first time I've EVER tried something like this. My biggest ally (and worse enemy) is Google, and I've lost count of the number of hours I've spent looking for something to gain access, even when its been staring me in the face I've still struggled (man have I struggled).
My point? the course material is good, but limited (like it's supposed to be) I've learnt more from trial and error or working it out myself than from anywhere else and for me it's the best way to learn.
I've spoken to people that have rooted most of the boxes in the labs, it doesn't bother me, I'm happy with my progress and what I've learnt and if I don't get them all then I don't get them all, it's not a race against others on the course it's a personal challenge.
If I'm honest, I expect to fail the exam the first time around, and I won't mind if I do (don't get me wrong I hope I pass), but this course isn't easy, nothing I read ahead of starting made it sound easy, but by god it's fun.
Anyway that's my speech over..

my only advice sternone would be regardless of how annoying/frustrating or annoying you find the course, enjoy the experience, learn what you can and when in doubt... Try Harder (sorry couldn't resist).
