Yes = buy it
No = Don't
Just because you can afford it doesn't really mean it's a good buy in particular.
Plus a lot of people interested in buying a founders package might not be privy to the requirements of the beta test. On top of this a founders package can run the cost of a (or several) price dropped games, or up to two new release titles. Having to choose between the lesser of two evils many people would rather and can more easily justify buying new games, rather than dropping cash for a beta. That said any fan who has the disposable income to buy a founders package might be well served to do so, and will more than likely do it.