Panda has time like domino but it doesn’t support backup battery. This means if you lose power then the clock get reseted. This is not an issue to most users.
Panda doesn’t have SD connector on board but it has support for SD. See this http://www.microframeworkprojects.com/index.php?title=SD_Card_Connection_Guide
If you need to use SD and do not want to do the wiring yourself then use domino.
Panda has USB clinet support and this is hwo you will load and debug your application. And you can still customize USB any way you like. This is same on domino and panda
Domino has USB host but not not panda. So, you can’t save files on a USB thumb drive on panda but you can on domino. This is the main difference. If you need to use a USB keyboard or USB memory stick then you need domino; otherwise, use panda.
Panda is not limited by an means when it comes to the internal chipset/support. It is just a lower cost version where we striped out few parts to lower the cost (nor RTC backup and no USB host)
Finally, you should take a closer look at this page please http://www.tinyclr.com/compare/
I hope this clears things out for you