Im currently on a 70-680 course with a training provider. Its one to one training so is quite intense and we've covered a lot of stuff, and probably wont get through all of the material during the 5 days we've got.
Luckily this isnt something we're being charged for and is funded by the government on this occasion so not too bad, but ive got the CBT nuggets for the course and have been watching these as a supplement to the actual course.
The tutor has taught me lots of stuff which wont necessarily be in the exam but things which he thinks he can add value too and will actually be useful in the workplace, but there is still a hell of a lot of material to get your head around and lots of key words, terminologies and phrases to settle with. Ive been doing ok with his end of module quizzes getting around 70% correct but i'm still going to give myself an addition 2 week after this week to continue studying before I take the test as we won't cover ALL of the material so i'll have to do a lot of it.
But has been said I think its invaluable to set yourself up with some VM's at home to test out some of the deployment options etc. On the whole its a good course so far and ive learnt a LOT but don't be fooled, it is A LOT of information to process and I personally don't think you'll be able to pass the exam just by reading the book. I think a mixture of reading the book, making notes, watching videos, doing PLENTY of practice questions and doing practice labs should see you through however!