I have been asked more times than I can count: why do you use Invision boards for your work on forumotion, and not PunBB or phpBB2? I have many reasons, and here's a few for you to think about.
Make no mistake, templates are a GREAT thing to use. They give you direct access to the page as it is being generated. This makes coding and scripting a LOT simpler, which in turn makes page loading and performace MUCH better. But here on forumotion, templates are only available for phpBB2 and PunBB.
I would never, EVER use phpBB2. Only a moron would use phpBB2. The code was written in the last millennium, and its DOM and CSS are so bad it is almost impossible to do more than basic manipulation. I honestly feel sorry for those people who have been duped into using phpBB2 so that they can get extra features through the templates. The only thing extra they have gotten is misery. forumotion should end support for this dinosaur of a board and make it as extinct as a dinosaur.
Next in line: PunBB. It's an improvement over phpBB2, but.....it has its own share of problems as well. Its DOM is a better design than phpBB2, but hard as it may be to believe, its CSS is worse. PunBB boards have BY FAR the worst CSS of all four forumotion board types. Its CSS is so bad that, on the one board I developed using PunBB, I rewrote most of the templates to convert its DOM to Invision, so I could use Invision CSS! It is easy to pick out PunBB boards by their ugly post displays. Reading and composing posts are the core functions of a discussion board, and for these functions, PunBB boards are by far the worst of the four forumotion board types.
Now we come to phpBB3, which is in my opinion a big step up from PunBB and phpBB2. The CSS is excellent, and most of the DOM is well thought out. Its big drawbacks are the use of definition lists for forum/topic displays, and there are too many individual elements left "hanging" without class/ID markups. If forumotion ever offered templates for phpBB3 but not Invision, I would switch to phpBB3 in a heartbeat because, unlike phpBB2 and PunBB, it is easy to correct the deficiencies of phpBB3 in the templates.
And finally, we come to Invision, which is a variant of Invision Power Board 2.0 (IPB2). Because forumotion does not use the IPB2 admin control panel, Invision Power Software (IPS) required that the IPS copyright be removed from forumotion IPB2/Invision boards. IPB2 has outstanding DOM and CSS, by far the best of the four boards on forumotion. It also has several features not found on the other three board types, such as drop-down displays on post profiles and memberlist entries, and a memberlist display that is 21st Century, as opposed to the 20th Century lists of the other three board types. The DOM is so well thought out that it is simple to write scripts to perform complex manipulations. It is also easy to manipulate virtually every element on a page through CSS.
Take a good look at the DionFM™ topics lists. Those lists are impossible to achieve on a phpBB3 board. The vBulletin-clone post display here would be impossible to achieve on a phpBB3 board. Both features can be done through templates, but the amount of work required on phpBB2 and PunBB templates would be much, MUCH more than what it took on an Invision board without templates!