[whpalmer4]

There are some things which will be less convenient without a copy of the Mac application, but you can get Omni support to help you over the bumps that absolutely require a Mac (creating perspectives, for example). Most of the things the Mac makes easier are what might be regarded as maintenance tasks, not things you need to do on an every day basis. If you've still got your copy of OmniFocus for the Mac, I think you would be in excellent shape, and only rarely need to use it. Most of my usage happens on the iPad, and the Mac usage splits about evenly between tasks where having a big screen is very helpful, tasks where I need to do some maintenance or need to run a script, and tasks that are simply more convenient to do on the Mac because other parts of the project need to be done there.

I believe the answer is yes, for most users it is feasible to use OmniFocus for iPad without OmniFocus for Mac. You have a 30 day guarantee of satisfaction with Omni products, even those bought from the iOS app store, so you do have a risk-free opportunity to verify that it will work for you.

I have little doubt that future revisions will make a standalone copy of OmniFocus for iPad even more powerful, but you should make your go/no go decision on what is available right now, as it is rarely possible to know when some other whizzy feature is going to come out. The good news is that Omni is very interested in feedback in how you think the product might be improved; the not quite as good news is that it can take quite a while before even a great idea with wide support emerges, as they have a lot on their plate and only a few forks with which to eat :-)