You do know that the less percentage equals a darker tint, right? 5% means the tint only allows 5% of light through. There is nothing below that OTHER than layering it twice or having factory dipped window tint and tinting the window 5%. 32% is legal in GA. Most people do a 25% on Sports cars b/c 20% looks pretty dark on most cars. If you have a light interior (grey/white) the lighter the tint will look from the outside so you'd be able to get away with 20%.
-Ant.