We liked access from places outside of the office.
We are a small building contractor. We switched over for three weeks and have switched back to the desktop. What did we dislike? Such a long list! First, it does not calculate taxes on payroll correctly. It only calculated withholding taxes on an employee's salary, not any of their taxable benefits. Second, lumps all federal taxes together instead of separate accounts for medicate, social security and withholding. Third, no way to distinguish Vendors from Subcontractors. Our "To Pay" report included too many entries for the report to be useful to our Subcontractor Supervisors. Fourth, no way to track Certificate of Insurance expiration dates for subcontractors. Fifth, calculated incorrect taxes for some state taxes. Sixth, no job costing reports by item available. Sixth, cannot save invoices as PDF so they can be stored on our Google Drive. Seventh, when database was uploaded from desktop, several old credit amounts (that were used) suddenly showed as available. QBO answer? Delete the credits. Hello? How am I going to do accurate job costing if I have to delete valid credits? Eighth, no progress invoicing.
Unless you have very simple accounting needs, don't do it.
We only solved the problem of how to have access to the financials from any location but the "cost" of what QB Online could not do was too great.