Cons: The switch from SilverLight to HTML has been slow and each release has been somewhat buggy initially after upgrading when using the new HTML pieces. Aside from that, the system is as good as your involvement and motivation to learn (especially during Implementation - be diligent and thorough in your discovery and scoping, or it will be painful when transferred to support).
Having used Dayforce HCM for over 5 years, I can honestly say that it is an incredible piece of software that is ever-expanding, and the developers are always hard at work creating more modules. As opposed to previous systems that required multiple file feeds internally, which would constantly update one place such as the HR record, but would not update in Payroll, Self Service, Benefits, or wouldn't update in any of them; with the Dayforce product however, there are no longer such data integrity issues, as it uses one database to house it all.
It also also far easier on the eyes than some previous systems I have used, and the ad-hoc reporting along with topic builder make creating custom reports quite easy (once you get the gist of how it works - there is a learning curve if you don't take the training - but if you're savvy, it's quite robust) There are still some options that could be improved in reporting, but is also improving. The key with the switch to Dayforce is IMPLEMENTATION. If you are not diligent, clear, and thorough with the discovery stage and throughout the implementation process, it will haunt you down the road. Make a team, someone from each module, and/or dedicate someone to nothing but testing and making sure you've got it doing what each team/department/manager/user needs it to do, anything you can to make sure you are comfortable with the application and get what you need out of it functionality-wise, otherwise you will spend a lot of time fixing issues with upset employees after you have gone live. Ceridian has grown their teams vastly, so the support reps can be hit and miss as far as their experience and confidence, but if you are techy and willing to learn the system, it is far superior to the others out there, and can be very low maintenance.