I think that one thing you have to take note of is that your widgets and other stuff won't immediately reflect the changes that SP is doing.
For instance, I have an @work profile that turns vibrate on my notifications and ringer during set hours mon - fri. I looked at my phone shortly after the profile activated one morning and one of my widgets showed my volume at max still.
I checked that the correct profile was in use, and it was. Right about then a gmail notification came in, and the phone only vibrated. A quick call from my office phone to my droid confirmed that the ringer was also on vibrate.
So if you use widgets to show the various settings on your phone just remember that they don't update in real-time with the SP change. Once I learned that I basically put my full trust in what SP told me the phone was set on.