I think I like the "belly band" best as long as it isn't "messy" in any way and no tape or anything is showing. The twine is really cool, but would need to still look elegant, like the one in the picture. I really do not like the tulle.
I like the belly band. I also like the tulle and ribbon, I'm not sure if the twine would match the elegance of most invitations.Something to consider is that if there is a knot on the invitation, like the bow on the ribbon, you will be charged extra at the post office. I don't remember exactly but I think we had to pay an extra 10 cents per inviation. Knots make the envelope bumpy and then it deosn't fit through their machines, so the charge is for hand stamping.
I think it really depends on your theme and how the rest of the invitations look. My friend had a barn wedding and used the twine for hers and it was perfect. But if your wedding is more elegant, I like the belly band too I think, then the tulle..
I was just thinking of what kind of ribbong to use for our invitations...they all look great! I do think it depends on your theme/venue :-) Good luck!
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