XO Communications is not a reputable company, IMO. It has been sued for engaging in deceptive advertising, as shown by certain class action lawsuits (google them).
XO has policies in place involving billing procedures that even when they admit they made a mistake on billing, once service is suspended it cannot, per its own internal policies, immediately return suspended service until the customer prepays next month's service bill. This happened to me, and when I called to find out what happened to my service, their "competent" staff troubleshooted it by referring my call to its tech support which opened a trouble ticket. Eventually Verizon even was called in to check on its part of the lines XO uses. Several lost days later, I am learning it was suspended due to an unpaid bill they sent to a previous address, and we had given them my updated business address on several occasions well before suspension.
Once I received the bill, I paid it and 5 days after the check was cleared in my account, they apparently suspended my service for a payment more than 90 days past due (even though it was only 60 days and change old, due to their billing address error). They claimed to have sent me a written warning, but it was sent to my previous address, and they also said they sent me a recorded call warning of the suspension but it was sent to my fax number that is to my Ricoh Afficio 4501 copier. I share one line, the fax, with another business. These warnings occurred after I s/w customer service about the missing bill and their emailing it to me in late November, whereupon I paid it.
When I learned of the reason, there were no overdue payments, and the current bill payment was already in the mail, well ahead of the due date (end of this month), and there never was a 90 day late payment. After complaining to customer service and the "collections" department, they all said they need my payment for the current month to clear before restoring my business service with the "Restore Department." I s/w "Steven," the manager in collections who was hard to reach (I had to insist, after being told the BS line he was not on the floor at that time, even though it was an hour before closing), who said he had absolutely no discretion, did not apologize for XO's screwing my business, refusing to change my billing address, for failing to let me know that XO was going to stop service, and for extending the problem by sending my issue to tech support and opening a trouble ticket of all things. I have been a loyal customer since 2000. This is how it treats loyal customers and refuses to correct its own errors.
XO is an incompetently run company, and its ineptitude has frozen a part of two businesses. Stay far, far away from this company, it has no soul, or concern for you the customer, even when it admits it erred and caused the problem.