It depends if you are wanting to go MD/DO, stats, when you want to start medical school, etc. If you want to apply MD and start medical school by fall 2018, then I would suggest option 2. If you want to apply DO and start medical school by fall 2018, then option 1 is reasonable and so is option 2. (obviously the earlier you can submit a full application the better, but August MCAT is still not considered too late for that cycle). If you are wanting to apply MD and go option 1, odds are you will have to wait until fall 2019 to start. (Spend summer 2018 applying, MD cycle is shorter). Personally, I feel Kaplan's biochemistry review book did a great job at covering biochemistry basics and very sufficient for the MCAT. If you did option 2, you would have to learn some of the biochemistry material ahead of schedule compared to in class. It all depends on what you personal set timeline.