If you're worried about getting too big quickly, then don't juice at all. Are you worried about people noticing a big size increase or something? Either way that's a pretty low dose and I wouldn't do it. The body doesn't produce more than 100 mg/wk test naturally, but what you'd be getting if you did this isn't much more. Correct me if I'm wrong but this will still shut you down and for 20 weeks!!?? Way too long bro. Up the dosage, shorten the length IMO. If you're worried about people noticing, then use some good e-management throughout.
Hope this helps.