Don't want to re-ignite the which nailer is best debate. Am looking at the DeWalt cordless 16 gauge/20 degree angled finish nailer. The new one is 20V; the older and cheaper is 18V. Both get good reviews but of course the 18V has a longer track record. Does the 20V vs 18V really make a difference or is this one time when I can buy the cheaper (but still pretty expensive) model? Appreciate your views/experience.