I have made my own variation where I do Chest and Rows, Shoulders and Lats, Arms, Legs and Trap, then repeat and take 1-2 days off a week wherever needed. It's not so much difficult it's just different, because I will do 3 supersets of a 10x10, so each superset takes 20-30 minutes and that is the part that sucks. Also I'm not really feeling to much muscle overload just a light pump. I'm thinking about maybe tweaking the workout where I'm doing 1-2 supersets of a 10x10 then do regular volume training like 5x15 for a greater range of exercises and really push hard.
What I'm doing now, though - the volume is there I just don't know if the muscle overload is enough to get any quality gains. Usually when I leave the gym I have a serious pump, muscle fatigue, and soreness the next day. With the GVT I am doing not really experiencing that.
What's the best way to do GVT to get serious gains?