Insulin adjustment with Symlin and adherence at insertion site

I have been wondering about people's experience with Symlin. Does a % reduction of mealtime bolus (i.e. 30%) work best when administering Symlin vs. same dose but different bolus type (i.e. dual-wave instead of normal)?

Also, what is the best way to keep insertion site secure? IV-3000? Has anyone discovered anything cheaper that works?