Same here (well, I don't have a Giant frame). I am gonna try a 120-130 stem shortly, and I will be shocked if it changes the handling of the bike significantly.

I am always between sizes too and went with a smaller frame this time. So far it has worked out very well. The key is to find a frame with a head tube that is tall enough so you don't need a tower of spacers to get the handlebar height correct, IMO.

Good luck.