I've been using Onedrive for some time but have known about Dropbox a long time, as well. I've had to download some files at Dropbox that I purchased. Both cloud storage systems offer free accounts with Onedrive being more economical for the value. Both services are also affiliated with Microsoft and Onedrive is free with a Microsoft account. I've been a longtime user of Outlook, so my Onedrive is through my email service.
I'm going to continue with Onedrive for now. Since Dropbox offers a free account, I'm going to sign up. It's such a popular cloud storage platform and I may need it in the future.
Casey Schmidt at Canto breaks down the pros and cons here:
