I'm curious about some things you said. Under the disadvantages of 1, you say: > II) you can't give customers what they want/need immediately even if they wan

I'm curious about some things you said. Under the disadvantages of 1, you say: > II) you can't give customers what they want/need immediately even if they want to pay for it right now as you need a significant improvements for the next version. That's true of subscription software, too. Developing any feature takes time, often a lot more time than you thought. It might be longer for the traditional model, but a feature that takes 2000 developer hours takes 2000 developer hours regardless of what your sales model is. Under 2, you say: > I)Everyone is on the newest version all the time How do you figure? Just because you offer an update doesn't mean people will install it. In fact, many pieces of software I use on a daily basis are "don't update until current project is finished" status. It can be very disruptive to install an update mid-project, especially if something goes wrong and breaks. It can also be really irritating. I remember reading that Valve releases something like 3 updates per week for Steam. I hate running Steam because it's always freaking updating and I have never seen an update that made any material difference to my use of the app. I literally can't tell anything has changed in most updates. Under 3 you say: > III)It's seems to be recipe for a situation where there are 100s of "current versions" people are running and that's very difficult to support. I think that's going to be the case no matter which sales model you use. (Well, maybe not hundreds, but several versions.) Most businesses decide to support the last n versions. If you're on an older version, it's no longer supported and you either need to update or migrate to something else if there's a problem. This can be fairly reasonable if you support a wide enough range, but there's always the push and pull of what the company can afford to support vs. what users want supported.