Peggy
in memoriam 2016
Its a personal preference. I do believe that you have to use platforms for what they are best at and designed for. Forums are designed to be just that forums. They are fast and reliable bulletin boards. When people start asking the developers to make them capable of operating the NASA space shuttle you end up getting a bloated product or not well thought out one since its hard to change the foundations for the most part of any framework as far as software is concerned. I do think that the WP as a front page and xF/VB/(you name it) is the best for a big site (or a site that you want to get big eventually).
The model gives you the best of both worlds and the support of both communities when it comes to resolving issues. It also gives you the most flexibility. The hit you take is with integration but there are plenty of big sites (VERY BIG) which work using that model and are quite successful.
As I said its a personal preference. I know many will disagree and argue that the Forums software should park your car as well as cook breakfast in the mourning while walking your dog and making plans for your next vacation.
ooohhh ok I gotcha. I am using XenPorta and XF. It's working very well.