ClickFunnels feels like it CAN do just about anything. It's funnel-builder is robust, the templates are incredibly helpful, and their email server (with or without Actionetics) is fairly powerful.
I think my favorite feature, however, is that you can share funnels. As a coach, a big part of my job is teaching network marketers how to build an online presence. Most of them have never heard of a funnel before, so this can be an uphill battle.
I love the fact that I can create a fully-featured funnel template, then just share that link with my students.
ClickFunnels feels about 10 years outdated. The interface is fairly ugly, and the whole user experience just feels ... Clunky, is probably the best word for it.
I think, more than anything, ClickFunnels suffers from massive feature bloat. Over the years, they've added SO MUCH functionality that it lost accessibility. Sure, you CAN do just about anything with ClickFunnels ... But it's not gonna be easy.
Expect to spend a TON of time on the (very outdated and incomplete) help pages, in the Facebook group, and talking to support (which has been surprisingly much better than I'd heard) ... And for a lot of the answers to be, "Oh, well, that's weird. That should work. I don't know why it isn't."
All-in-all, it just feels patched together and what seems like a simple processes just become unnecessarily difficult and frustrating.
Honestly, I've thought a couple times about quitting and rebuilding everything somewhere else. Somewhere more user friendly. But the fact of the matter is, while there may be tools that are easier to use, none of them are as powerful or as versatile as ClickFunnels.