The response time certainly averages less than one hour (but could be longer at times). Officially our hours of support are UK office hours but we do have staff that respond to support requests outside of these times.
There is no online chat.
There is no documented support agreement aside from what is mentioned in our License Agreement:
For the initial twelve months of the License (“Initial Period”), which shall commence upon payment by You of the applicable license Fee, We shall provide You with support to respond to any problems (“Support”) You are experiencing with the Software which result in it not complying with its description or the demonstration, as made available on Our website (“Problem”). Such Support and all software updates ("Updates") are included in the License Fee for the Initial Period. Additional payments ("Extension Payments") will be required to extend access to Support and Updates beyond the Initial Period.
You may notify Us of Problems via the website and We will use Our reasonable endeavours to respond to such Problems and provide a resolution to such Problems. For the avoidance of doubt, We do not warrant that We can provide resolution to Problems on an individual basis and resolution to Problems may be provided with the next Update.
I have been using XenForo software for the last 18 months and the support both from staff and members is outstanding.
The software usually works as specified and if there is a bug, the developers are very good at getting things fixed.
I switched to XenForo from another forum software company and the difference was a pleasant night and day difference to me.
Xenforo is a great forum software. I've used MyBB, PHPBB, Simple Machines Forum, and Invision Power board (wouldn't touch vBulletin with a 10ft pole) and Xenforo is the only system I have been impressed by.
I've been using XF for a few years.. and just got a copy of IPS (new IP.Board). I guess I got spoiled to the level of help here from the staff and members. Went over to IPS support forum and posted a few questions and they went unanswered for much longer than they would here. Also entered a ticket and if I hadn't of PM'd one of the staff it would probably have taken 2-3 days to get a response - and it wasn't anything minor but a collation issue that was throwing an error. Ended up fixing it myself.
It's not.. it's vary rare that a post doesn't get a reply - I've seen a few, but the questions were usually so esoteric that not many people would be able to answer them.
Also, it's useful to search for the primary phrases in any question(s) as they have probably been answered before. For multiple words, just use the pipe symbol between them - that is the | which is above the / on a US keyboard layout.