They're still on version 2.0 after having it released in
2018.
They're on version 2.3, which is a significant difference, as second-point releases have added features, while 3rd point (2.0.0 -> 2.0.1) only addresses bug fixes.
Going from 2.4 (the next 2nd point release) to 3.0 will be a 1st point release because it has a significant change that we can expect in the style, with perhaps even more features than 2.4 (or 2.5 as they suggested) too. I hope that the style brings it more up-to-date with social media-like interaction and navigation, but I'm not really holding my breath on that.
Either way, I think XenForo is the best as you can easily add any feature that any other forum software has. It just costs you time to learn or money to outsource it.
Invision is something like $200 every 2 years or your license is suspended? No thanks. I have some licenses still on 2.2 (one on 2.0) that are expired, and 2.0/2.2 works just fine for a starter community. Why pay to upgrade the license and launch on 2.3 when I can do it for "free" on 2.2, then pay the $60+ to upgrade to 2.3/2.4/3.0 after it grows enough? I might be wrong about the license being suspended,
@AWS could fill in if I'm wrong here.
To me "Xenforo is just a forum" is not how I look at it: It's a complete engine. I could turn off the forum on
Forum Directory and have it work solely as a forum directory with listings, etc. with the add on it uses to accomplish that.
To further expand on that, with one example, I also have intentions to build a text-based game on it (possibly, as I'm still investigating other engines and their capabilities with user groups/permissions/etc.), and looking into "Allowed thread types" (Discussions, Polls, Articles, Questions) to expanding that to "MAP" (in a custom add on). This is so that I can build out a grid of 1000x1000 (1,000,000 "threads") with custom fields in the "MAP" to execute different tasks, like finding in-game money, for instance. The forum display wouldn't be how it is as a forum, rather a 1000x1000 "image" (each image like 10px x 10px to make up a full image with 1,000,000 threads) and you can start at position 1,1, but only move into thread 2,1 or 1,2 from there to see what's in that location on the MAP with your Avatar overlayed on the map where you are.
A quick mock-up of thread types being a MAP in the forum view:
I could move to red (2, 1) in thread "2" or green (2, 1) in thread "1001". Each thread would have an event executed, or nothing at all, when visited, and I would limit moves per day.
So much to do outside the box from a traditional forum on XenForo compared to alternatives.
If Invision lets you develop, it could hypothetically do the same, but it wouldn't be cost-effective with the developers I could take on for XF over Invision.
I also plan on a Project Management System with the full 9 yards like Ghant charting, etc., which would have "forums" so different projects could have a discussion area, but it wouldn't be a "just a forum" at that point either.
Granted, if you had to choose, choose what's best for you, as you need to keep an open mind that it will take a lot of time and/or money to get XenForo to where you want it to be, but it could be at Invision's level with the right work behind it (if that's what you were going for), or you could just choose Invision from the beginning.