Save the Date Ideas

I am deciding between two ideas for my save the dates. 1.) A business card or 2.) A postcard.
My wedding colors and navy and yellow.

Lemons
For this one I can use any colors I want

Simple enough w/ navy blue writing

postcard

I am really pushing more towards business cards. That way people can stick them on their fridge and forget about it. Plus it's a lot cheaper. 100 personalized business cards range from $6.99-$20 for 100. All I did to find these templates was type in "make your own business cards" or "design your own business card" into a search engine. I then searched thousands of templates. There are so many ideas out there. I think I reallllly like the lemon one. super cute and different.