what is the best size gps/depth finder micro sd card size?

[keakar]

just not sure how much data storage space the average guy needs so what is a good sized card to get so I know I will only use 25-50% of its storage space?

I "assume" I will only be saving a bunch of way points and the occasional down scan image but admittedly I am clueless about what my data storage needs will be because this is the first time I ever had a gps or anything with the ability to store data

I have the elite 5 hdi gps

so I guess the real question is, what size micro sd card data do you need space for and then based on that, what size micro sd card should you buy?