I am all-in on Agenda, but not exclusively.
By that I mean, I’m using Agenda all day, every day. It has quickly become my most-used app. I take a lot of notes throughout the day, and most of them are based around dates / times, so Agenda works great for that.
I still use OmniFocus daily. But, I’ve been able to trim it back quite a lot. I don’t try to do any sort of planning in OF. It is still great at organizing actions using tags, and repeating actions, neither of which Agenda really does.
I link or duplicate between Agenda and OF pretty regularly. So like for a project, I’ll do my planning in Agenda. I’ll make a checklist of the high-level milestones that I need to hit. I can then either work through that checklist, or add an item as an action to OF, or an item might even become a project in OF. So OF projects now become smaller chunks than they used to be.
OF is great at slicing and dicing a bunch of stuff. But, I’ve never felt like I was able to get a good understanding of context – and I think I’ve been using OF regularly for 11 years or so. Two key questions – “what have I done?” and “what do I plan to do?” – have just completely evaded me in OF all this time.
So, I use them together, and I’m still working it out, but so far it’s good. Agenda can be a lot more ad-hoc, less strictly structured than OF, and so I’m able to use them together in a pretty fluid fashion.