e140 is very good value, depending on the coverage/terms & conditions. Might be worth your while to compare it to one of the packages available on the market.
Some people might say that it is a very negative way to lead your life, when you fork out money for eventualities like serious illness; others look at it as essential.
I personally took out serious illness cover. Even though hospital costs would be covered by VHI, there could be long-term costs, e.g. if you end up in a wheel chair permanently, you would need money to convert a car, make you house more wheelchair friendly, etc. If you have a family this would be particularly important.
As I said though, it is a personal decision.