Yeah. This is all a matter of opinion and what works and is convenient for the individual. I use high gi carbs before a workout. As long as you don't wait more than 15 minutes or so before hitting it you won't have a sugar crash and even if you start to your blood sugar will should balance itself out fairly quickly once you start lifting.
Slow carbs an hour before are great too. For pre workout my advice is to do whatever WORKS for your body, your schedule, and gives you the best performance in the gym. Second guessing and nitpicking things like insulin spikes before your workout is secondary to all that. If you start getting really fat or something that may be a better criteria
