Unlimit your business with Google Drive for Work: Official Google Enterprise Blog

Unlimited > Microsoft's OneDrive terabyte per Office 365 user (announced for Office 365 ProPlus customers in April; Office 365 Home customers also now get a terabyte), although Google Drive for Work customer organizations with less than 5 users get a mere terabyte

"But we’ve also heard from businesses that they want more control and security, visibility into how files are shared, and a product that will grow with them. So we’ve been working to make Drive even better for business, and today at Google I/O we announced Google Drive for Work — a new premium offering for businesses that includes unlimited storage, advanced audit reporting and new security controls for $10/user/month."

Official Google Enterprise Blog