DA/SA systems require, by definition, that you use the two trigger pulls together. If the shooting starts, most of the rounds will probably be fired SA, but the first and most important one will be fired DA.
Once you're comfortable with the gun, if you're having any problem with the double action shots hitting, dedicate a substantial range session to a drill of fire, decock, fire, decock, etc. This will help habituate your trigger finger to the longer, heavier first shot pull that starts with the trigger more forward. Soon your hand and trigger will figure out that they are manipulating two guns: a double action SIG, and a single action SIG...and will be able to pull each type of trigger set effectively upon demand.
Be sure to habituate yourself to decock any time you change position or otherwise have a "lull in the action."
I've personally found that the transition from double action first shot to single action followups is facilitated by getting the finger deep enough onto the trigger that it's contacting it on the first joint (distal joint), not the pad or the tip. This gives the hand more leverage.
Don't worry about the longer re-set. Split the difference between trigger slap (finger comes off the trigger every shot, whacks it on the next) and riding the link or sear (finger tries to let the trigger come forward just enough to re-set, not famous for working well under extreme stress), and go with the middle ground of "trigger weld": maintain finger to trigger contact while sustaining continuous fire, but let the trigger come forward until it stops moving before beginning the next pull.
This is true of any DA/SA pistol, not just the SIG.
You've chosen a fine gun. Use it in good health. The very fact that you asked about this tells me you're committed to using it well, and that is A Good Thing. :-)