There have been times where I seriously considered buying the screensave in the past, but always decided against it. Basically, the reason was because there was always a new version or new features in the works, but buying the currrent version meant I would have to pay for the new features later on.
For a smaller software investment, I don't really like having to go through lots of upgrade purchases. If there was someway I could buy the program once and be assured of the updates.... Or, at the very least, maybe being allowed to buy version 2.6 now, and be offered free upgrades up to, but not including 4.0 (so that way I'd get version 3).
Don't suppose you would consider this?
