Departure/arrival immigration/security lines depend on how correlated your flight is with the major blocks of inbound/outbound flights. It can be 3 minutes or 45 minutes depending on your flight times. I've flown to TPE many times over the past 20 years and don't think I've ever waited longer than 45minutes.
In my experience, NRT/HND/ICN/HKG are all comparable and have the same variations.
Of course, for frequent travelers, at TPE you can apply for a free permit that gets you Fast track immigration and from gate to Xinyi hotels in <1hr including luggage pickup. I haven't seen this elsewhere in Asia and is far better than ICN or NRT... The same permit works for departures, but security is the bottleneck so it doesn't help much.