Well... probably a little bit, just because the nicotine content is a bit lower. At a drop of only 4mg it shouldn't be too drastically different, and it may be as much psychological as actual.
If you're concerned about the lack of throat hit, you could always mix the two at 50/50. Then if it isn't too much of a drop in TH for you, add in the additional 7-8ml of 18mg.