30 minutes? How come? You take a at least 1.5 minute break between every set. So for 5 sets of first exercise that's 7.5 minutes assuming you don't take longer breaks and that you didn't do any warmup and just went straight for proper weights. Now add exercise itself and it's easily 9 minutes. Times three (again, assuming you don't take longer breaks which is really hard to do when you start hitting heavier weights) and it's 27 minutes. Add warmup and stretching and it's easily around 40 minutes. I think my fastest stronglift session was around 50-60 minutes. The longest was easily over 2 hours. When I started hitting squats with weights around 1.4 my body mass just warmups and proper sets were 50 minutes in itself. That was about 11 sets of squats with some breaks being 3-5 minutes ones.