I did my XFMG import from my vBulletin 4.2.4 a couple of months after I did the main forum import, and it was fine. I know that XF has made some improvements to the XFMG importer this year, but after I did mine, to make it even better.
There are a number of threads here on this forum about how folks did their imports from vB. I did mine probably the most radical way possible -- from one domain on a hosted site to a VPS with a new domain with another, different provider.
The most important thing you can do is the planning, up front. The planning, and 2-3 "test" imports, will be invaluable in working out the bugs and kinks in the process. The XF importer from vBulletin 4.X handles the actual import very nicely and accurately, as long as it is set up correctly. Doing a couple of "test" imports is imperative !!
I found the biggest issue was post-migration -- going methodically through the new forum's settings and tweaking them so that they were essentially the same as the old forum. This takes some doing, as the settings are different than vB, and found in different places. In some ways, vB was better in this regard, and in other ways, XF is better. It's more a matter of familiarity with vB and how it is set up and does things, and then having to "re-learn" a lot of things with XF. Generally XF is more flexible, but there is a learning curve with the admin control panel and settings.
Again, I found that XF brought over most of the user groups and settings and permissions pretty well from vB, but I still definitely had to go through things after the migration, sometimes multiple times.
Another thing is that you will want to research and add some "add-ons" to add functionality that was previously found "stock" in vBulletin. Things like "who visited this thread" "who visited this forum today" "most users who visited ever" and that type of thing.
Lastly, I HIGHLY recommend, if you are using a VPS, buying and implementing the XenForo Enhanced Search add-on. This requires installing Java and the ElasticSearch engine on your VPS, but this is a really neat add-on that beats anything that vB ever had, hands down. I used Google Custom Search on my vB install, and I find ElasticSearch is better. There are a couple of add-ons from well-established developers (you can find them on this forum) that also provide additional enhancements to ElasticSearch, which are fully customizable and configurable and very nice additions.
I hope this was helpful. This forum's members and the XF moderators (such as
@Brogan) and developers have always been super accessible, super helpful, and super fast at providing advice and support. Even technical questions!! I also find that 80% of the time, the questions that I have, have already been asked/answered. Most recently, I had a member in Australia, named
@Sim, assist me with implementing a block storage volume to offload all of my file/image attachments off of my main VPS SSD drive.
@Sim went out of his way, after giving me the pointers I needed based on his own experience, to write up a highly detailed and illustrated tutorial on the topic, and post it here.
So there is a LOT of information here that will answer just about any question you have. Here is one such thread, of many.
I have a discussion forum with about 1.5M posts using vBulletin 3.8. I've been running it for nearly 20 years now and have thought about the possibility of upgrading the software. My fears are this: Could it hammer my rankings?
xenforo.com
WooCommerce with WordPress. It will likely be a month or two before considering a forum. LW is top-notch in tech support.
