I noticed that SigWxAdvisories (SPSs) show up fine shortly after they're issued, but they don't always drop off at the right time. This can leave the screen very cluttered since SPSs are one of the weird products that can't be edited or cancelled once they're issued or replaced by a SVR.
Here's an example of a screenshot I just took where the highlighted SPS expired but is still displayed after the placefile updated. The SPS expired at :30 after the hour, and the placefile was updated at :31. I know this particular case may be nit-picky, but they regularly hang around for 15+ minutes after expiration--It's still on there 9 minutes later.