For me both, i used bitcoin as currency and investment.
As currency, i used it to buy load shopping online.
And as investment ofcourse, i used it to earn more btc in
investment.
currently im use itcoin for payment processor only, for investment i choose other crypto curency like ethereum classic.
bitcoin is very simple to be a payment processor, easy to use tha paypal
you are right and use bitcoin as a better payment option like me . since i am.using bitcoin as investment but it is a work of patience to get profit . but overall i like bitcoin to find it as internet currency