I personally am not a fan of exclusive digital download, although I much prefer that than selling out to a corrupt publisher. Ideally, a game is available with both a hard retail version (the traditional box in stores) and a digital download with no lifetime activation limit. To prevent widespread copying with the latter, there can be a monthly activation limit. For an example, the game Mount & Blade has no lifetime activation limit, but you can only activate the game twice every six months. If you happen to need to do so more than that, you can contact the developer and explain the situation to them. At least, that's how I recall it working. It's not 100% ideal, but it works fairly well (unlike Mass Effect's five lifetime activations, meaning that if you reinstall Windows five times, you can't play the game anymore without first successfully haggling with E.A. on an expensive telephone number).
What I most dislike is any distribution method or D.R.M. which prevents a paying customer from being able to use the game or simulator at any point in the future, or which takes liberties with the security of the computer. I must refuse to support any developer who, at any point in time, utilizes such a scheme. It is very unethical and unfair to the paying customer; in fact, it punishes the customers for supporting the company, and gives everyone incentive to pirate the game instead. If I buy a game, it's mine for good. And no one dicks with my computer's security if I can help it.
So, as mentioned in the other thread, I very much hope to be able to support Thunder Works and fly Jet Thunder, but if Thunder Works finds itself forced to use one of the immoral D.R.M. methods such as those I've mentioned, I shall inescapably find myself forced to withhold support and go without flying yet another of the precious few high-fidelity aerial combat simulators.