It has loads of potential but it's early days yet as far as results go. Rob is giving it a good go. Pop on over to the Max-stim forum and ask stuff there plus there's a faie bit to read now.
My limited experience gained at the end of last cycle was that I managed 20 reps in a row with my 5RM weight for curls by managing my M-time. It wasn't easy but fatiigue was definitely lower afterwards than if I'd tried four sets of 5RMs (infact I would have had to have clustered to get 20 reps anyway) and I was left with a feeling similar to what I get when I do heavy negatives - a deep strain sensation.
I am going to try a Max-stim cycle once I have a few more HST cycles under my belt.