Is it okay that my son uses a soft spouted sippy instead of a hard one?

He's almost 11 months and has simply gotten used to this type (gerber's nuk brand) of sippy. I've tried a few times to see if he would use the other types (in many different brands), but he seems to only like "his" sippy. Will I run into any problems in the future by him not using a sippy w/ the traditional hard spout?