This afternoon I was at a Sony Store to buy some blank DVDs.
And funnily enough, I was asking the same question to one of the sales assistant there. He answered with "DVD-Rs are more openly compatible to a wider range of player devices. Capacity wise, they have no differences." I believed him, so I grab that one instead of the +R variant.
Afterwards, it worked fine with my MacBook.
By the way, both DVD-R and DVD+R have identical price tags at the Sony Store.