Ask HN: Double Entry Bookkeeping SaaS Recommendations ?

I work remotely with a partner on our business. With Google Docs / SVN /etc... staying in sync to each other hasn't really been a problem - now that we actually have expenses/revenues we need a good SaaS bookkeeping system.

I've have found the following players in SaaS space:

http://outright.com/ http://lessaccounting.com/ http://www.clarityaccounting.com/ http://www.ubikwiti.com/ http://www.xero.com http://quickbooksonline.intuit.com/finance-accounting-solutions/

Anyone have any comments / experiences with any of the above? Any recommendations of services not on this list?

(Note: Freshbooks and similar invoice services do not offer double entry bookkeeping)