I like how easy you can access all of my information, including past paychecks! Also love being able to send out emails without having them printed & sent back through email again- saves time!! It's also very intuitive when sending checks as well - makes things quick for us! The only thing i dislike about this program are some security issues they have had recently, but everything gets fixed quickly once notified by customer service team! We use ONESOFT at our small business (P&S Furniture) so we don't really see any downsides other than waiting till next payday or bank transfer instead of using online banking system.
As soon as something comes up regarding payment processing/security issues, onesoft updates their site immediately after notification from support staff member.