@squatter: I skipped the BC and went straight into IM (I was learning myself before I found justin) and in the end I mixed the IM with the BC. Some people progress relatively fast, others dont.
It took me to complete IM (+BC stuff that I wanted to learn) about 6 months, but I practiced every day, MADE time to practice and didnt have alot of issues with sore fingers, blisters (just a bit hehe) or grips. It all just happened for me on the acoustic and on the electric its so friggin' easy now.
I dont miss alot of days practicing now, even if its only for 15 minutes doing speed training and finger dexterity. every bit helps
Oh and, the 4-5months I was playing before was NOTHING compared to the progress I made with the IM/BC course of Justin 6 months after that. If I only knew from the start.
I'm still a beginner though