It depends on you, your flight times, what carrier you will be flying, and your destination airport.
The Businees Class lounges for Asiana at Incheon Airport are terrible, and their First Class lounges aren't much better. Asiana's idea of business class food is ramen noodles. Unfortunately, the selection of wine and spirits is on the same level as their food.
If you will be needing a shower or a slumberette, due to travel times. etc., I would say, it is a good idea. However, if you won't be needing either, there isn't much point.
Joining a mileage program and being faithful to the carriers in that program can get you access to their lounge for a modest fee, mileage, or rewards.
Bottom line, you have other options to get access.
Best of luck.