Most cookies and biscuits shouldn't have any problem with sticking even when placed on a non-stick sheet, though you may need to be more careful with burning the bottoms when you're not using a silpat or parchment.
"If it's chicken, chicken a la king. If it's fish, fish a la king. If it's turkey, fish a la king." -Bender
I have always found that when baking cookies that if I double pan them they come out better. think it is because most oven heat comes from bottom, so bottom cooks first. Second I believe that by double panning you have a small layer of air between pans and this helps insulate from direct heat.