I participate in a Zenforo forum and like the way it works. I had a hunch it was good, well-written software. And I still do for that matter. But good software is only half the picture.
I bought the entry level download for $140 and then added an "extended search" module for another $50. When my PayPal echeck for $190 USA dollars cleared I was sent a login name and password, which worked--but only for the download. Explanation follows.
Installing the base system on Mint Linux localhost was a breeze. I have 15,000 posts from a Phorum forum I would have to convert first, before going live. I had a plan. Xenforo has a free "resources" importer for SMF. SMF has a phorum importer. SMF is free. So I thought I'd use the Zenforo SMF importer in a two-step dance: Phorum to SMF, SMF to Xenforo. I could always hack the code a bit if I had to. My original Phorum posts came from a Bulletin Board I wrote myself.
But when I tried to download the SMF importer I was told I didn't have permission. What? I bought the software? I sent email to support twice over two days. Received no answer. I reluctantly made a PayPal dispute and immediately got a terse answer saying I had to do some non-intuitive add password to something step. I'm sure I could have done that. But that product support attitude pissed me off.
So I asked for a refund. I sell online with PayPal and my policy is to grant refunds no matter what. I get about a half a dozen requests a year. Xenforo offered me $150 on the $190 I spent. I accepted. A long term relationship with that attitude is not something I care to be involved in.