My last experience was exactly two years ago and it was a madhouse. I arrived at 12:15pm from TPE and waited a really long time in line as it seemed there were multiple mainland China flights arriving at the same time and that held things up. I had a 5 hour layover and was hoping to run out for a bit but had only minimal time after the immigration delay.

Perhaps you'll be arriving at a less busy time or they've straightened out the process. I was really surprised by how many people there were and how long it took!