It can always be a gamble when you pay for a computer game. You never know how much you will like it and how often you will play it and therefore you cannot calculate the value for money. However, it is obvious that if you buy a game and hardly play it, you will not be getting good value for money.
It is therefore better to not pay very much for the games that you play. This will mean that you will get better value for money because you will not have such a big outlay at the beginning. It will be even better if you do not pay anything at all.
The great thing about flash games is that many of them are free. And you can easily choose your favorite airplane games or tank games at thepcaa.org. This means that you do not have to consider whether you will like them or not or how much they will cost. It is possible to try as many of them as you want to without any worry about how much money it will cost as they are free. You can try out many games in different genre and see which you like. You may like certain types of games but by trying different ones you may find that you like more than you realised.
Some people would argue that because there are so many best friv games available to play then there is no need to spend any money on them at all. If you do not have the money to spend on games, then this will be ideal for you. However, if you do have a budget for leisure then it could be worth buying some flash games but it is always worth trying out the free ones first. You may find these are as good or perhaps even better.