I outline mostly as a first step for project planning and sometimes moves on to Microsoft Project if the complexity of the project is warranted. I currently use OmniOutliner 4 and want to upgrade to OmniOutliner5 Pro for $50 or just buy OmniOutliner Essentials for $20. Has anyone wished later that they should of both the Pro version instead of Essentials? If that was the cases can you tell me some specifics of why? I work in a mostly Microsoft Windows/Office 365 environment at work, does anyone find the export to Excel or Word a helpful feature?
Thanks
Bill
Depends on what you want to do. If you work mainly in Windows then perhaps look for something in that domain that works for you?
If you don’t need columns you probably don’t need Pro.
Word on Windows has good outlining features.
Not sure if OmniGroup provides an upgrade from Essentials to Pro with OO5, but they might – ask them.
I like OmniOutliner because it’s simplicity and flexibility to move things around. I have never been a big fan of Word for just anything except just basic document development. I will take a stab at outlining in Word, maybe it is good enough. I have never used anything but the basic outlining features in a tree like structure, what is the benefit of columns? The Excel export feature seems like a good feature mostly because I am a big fan of Excel and I can see how I could possibly use it. You bring up a great point about the upgrade from Essentials to Pro, I will give them a call. Thank you for your feedback it has been very helpful.
Bill
I have Essentials and they offer $79.99 to upgrade to pro. So you actually save a penny by going Essentials -> Pro ($19.99+79.99) rather than Pro directly ($99.99.) 
Be aware that if on iOS you want to edit and not just view your outlines you’ll need to unlock/buy the pro iOS app, which I think is $50 now.
I bout the Mac Pro app when it was $50. It has some unique features (like columns) but otherwise is a fairly clunky app with unintuitive ways to create templates to personalize the font/size/look.
I would not pay $100 for it today, and definitely not $150 for Mac/iOS connectivity.
These days I’d suggest looking at the surprisingly powerful free tier of Dynalist’s service, or if you want something Mac/iOS-specific is look at Outlinely or Cloud Outliner (Pro), both of which are in the app stores.
Sorry, that’s what I was asking you: if you don’t have a reason to use columns, then you probably don’t need Pro.
Thank you for all of your feedback.
I am going to purchase the OmniOutliner Essentials version mostly because it is good enough for 99% of what I plan to do. The Pro version features look interesting, but I do not see this is an “all in one tool” for everything. Hopefully I am correct !