During my trip in January 2019 to Taiwan, took the HSR to travel between 2 cities as I flew in via Taoyuan International Airport and our via KaoHsiung International Airport.
The entire journey on the HSR took less than 2 hours and it was quite a good experience.
Bought my HSR at a discount from Klook and cashback via Shopback. They offer different travel passes that allows flexibility to book the HSR tickets anytime and at a fixed rate vs buying from the ticketing counter.
While the train moves at quite a fast speed – 300km/h (186mph), the views along the tracks still looks pretty pleasant. Food service is also available from the push carts (only during lunch hour train) and vending machines. Alternative, you could pack your own lunch bento. The train departs on time so be sure to be at least 15 minutes early.
Arriving at Zuoying station, just exit through the designated gantry and walk towards the KMRT. The entire journey is quite a breeze and seamless access for transportation.
For more information on how to use Shopback, you may check out this article here.