Beware!
Ok if you don't mind losing your work
Edits well, lacks bank features
Upon startup, screen looks just like the Mac version of the editor. You have to set the MIDI channel for the P8.
Then set the MIDI in/out ports, the app does a scan at that point to verify connection.
Bank Tab.
It loads the banks from my P8 without mangling the names. So far so good. You can save banks to a file. Amusingly the file save dialog gives what appears to be the full internal iPad path to the file (/var/mobile/foo/longgarblefoo/....) instead of a more standard dialog. Not so amusingly, the on-screen iPad keyboard covers up the file name box, so you can't see what you are typing. Also non-amusing - an option to download 'Bank C' from the P8. Attempting to do this crashes the app.
I'm not seeing any obvious way to re-arrange the patches within a bank, nor any way to import a single patch into a bank, so I'd say -1 if you need a bank editor primarily, rather than a librarian.
And now we see why it's SoundTower - attaching the iPad to my Mac reveals there's no way to pull the files off the iPad! The app doesn't appear in the list of apps with Documents. Special!
So, i'd say -2 for that little bit. I am going to have to research this path in the load/save dialogs, maybe there's a way to get your data outside the app. So, I doubt you can import patches into the desktop version. Likewise, looks like there's no way to take a patch file from some external source and load it into the app.
Tap on a patch in the bank tab, and the P8 loads it, no hesitation. (This is banks already internal to P8, haven't tried to upload yet) Looks useable for reviewing patches in a bank.
Edit Tab
For a patch editor, not bad so far. Appears to track the physical P8 well. You touch an area in the editor (OSC, Amp, Filter, Mod) and that bit zooms up to useable size.
Doesn't appear to be any way to enter numerical values, all knobs. For text fields such as Mod Destination, tap and a list of possible options comes up.
I haven't used the Mac version of the P8 editor in awhile, because horribleness. Compared to my recollection of that goop, the iPad app seems to be better connected to the P8, no hesitation. However, it is Soundtower... the OSC pitch values were two octaves off (P8 = C2, iPad = C4) and hitting the Help button takes you to a 404 page.
I like having GUI editors so I can see things, I think it will work for that and patch editing. Hopefully, updates will happen.