I recently asked my tech what to do about sticky pads. He explained that he isn't a fan of powders because they build up residue on the pads that contribute to more stickiness. I have used a few powder products in the past, and do believe the same thing. In addition, he avoids using lighter fluid because it dries out the leather. I've tried this method a few times, but it seems to be only minimally effective. His suggestion was to use a microgrit sandpaper, and pass the grit side over the actual tonehole one or two times. This removes the built up gunk on the tone hole which contributes to sticky pads. His suggestion was to use P240/240 sandpaper or finer, and only use moderate pressure. I asked if this method would in any way damage the tonehole itself, but was assured that I would really have to try to damage the toneholes with this grit. I've been using this method for about 3 months now, and it has by far been the most effective approach.
(Edit) Of course, you must be careful to avoid scratching the lacquered areas of the horn.