SPL DE-Verb and Transient Designer works pretty much the same way as an expander in how it removes air and tails, only you have less control, as they both affect all sound no matter the volume or frequency.. although they are great tools, they have limited use when cleaning up sound.. if you for example want to clean up a drumtrack where you want to keep the boomy tail of a kick or tom, it is going to shorten those tails too, as well as everything else... with multiband, you can remove certain frequencies without affecting everything else
you can do the same with the SPL ones, but then you'd have to start to frequency split the audio
I suggested to SPL on their facebook page that they should do some multiband versions of their transient designers and they replied and said they'd look into it.. that was some time ago though.. doubt anything happened with that
there are some multiband transient shapers out there though, id like to try out this one some time -
http://www.musicradar.com/gear/tech/com ... ent-260579