Yes, it takes that long!!! We came in from Osaka-Itami. And if you just miss the xfer bus, you can add 14 minutes to that given the 15m cadence in the sked. The bus makes 3 scheduled, timed stops if I recall, and two tricky U-turns, then hauls under the runway for probably 1-2 km to get to the remote terminal 3. After that, you go through exit immigration (which goes fast), after which you are free to run to your gate.