So far so good! Control pages load quickly.
Two comments regarding linked switches:
If switch A controls a light, and switch B is linked to switch A, toggling switch B from IndigoTouch does not control the light. This is not a real problem, except that the white LEDs on switch B don't get updated when you toggle switch A from IndigoTouch, so they don't indicate the status of the light.
Similarly, if Indigo is programmed to turn on the light connected to switch C whenever switch D is manually turned on, activating switch D from IndigoTouch doesn't activated the trigger to turn on switch C. This may be a good design decision — I'm not sure yet which way I would prefer it, bit I wanted to make a note of it.
One other note: When installing the app, iTunes appeared to hang for several minutes with the progress bar for downloading a podcast showing about 99% complete. I nearly did a force quit on iTunes, but it finally finished. (I assume it was loading Indigo Touch during this time.) This sound like an iTunes problem, but everyone should be aware of this possibility and just wait for it to finish.