x2. 20iu is a lot. You could end up "in the trees" rather easily. 5 to 10 is more typical. The consensus is that longer slins R and N are more forgiving than the rapid-acting ones and a better bet if you are not very experienced. Be careful.
There is no reason to "work up to" a certain dose of insulin....3-5ius will have a fantastic affect on blunting cortisol and increasing lbm and strength gains.....dat had a study posted in his thread which basically shows how over 7-9ius has a negative affect on gh senstivity....but under that threshold has a positive affect