DO higher offset wheels make a difference?
 

or is it barely noticeable... i am using 5.5T brushless setup with lipo

Of course they make a difference; they change your setup. A larger offset will make the track width wider. Same as adding wheel spacers. As for how that will effect handling, you should consult a setup guide.

*edit: The Hudy setup guide says that increasing front and rear track width will cause a substantial increase in understeer...

so it will be more stable?

Yes, the wider you make the track width the more stable that end of the car will be. The narrower it is, the more nimble and responsive that end of the car will be.