"Paid forum posting" associates with me with services that offer forum administrators posters (writers) that populate forum with content. What you are referring to, simply, is advertising. Whether it comes in the form of a sticky ad, a text link, a built-in text-based sponsorship position is a secondary matter. The only difference is that sticky ads naturally integrate into community and stand out in a more organic way to those people that visit, read and participate in forums.
We occasionally find positions that we see value in, but the objectives we set for them may differ. The exposure and awareness of our brand in certain markets is important to us, irrelevant of the ROI it brings. If you are dead set on increasing chances for a return, I don't imagine you can convert anything on a short-run sticky campaign, unless it is a very limited and an aggressively discounted promotion. In general, the more people know you over time, the more comfortable they will be to choose you. Then there is a question of financial ability to support a lengthy campaign like this. Not sure what WHT is charging these days, but I've seen sticky pricing there go for up to $1000/week in a Dedicated Offers section I believe. Compare that with any other forum and see if the value you get is at the same multiplier. Seeing a larger number of pinned advertising posts here on this forum may be an indicator of better value.
