I haven't really been boosting lately, so I know back in the day, it was mostly miss (than hit) with the boosts for some people. Since I most recently came back to play, was curious to see the state of them before I make a purchase on the Boost Sale. :)
I know that the general rule of thumb was that the static boosts (Eternity Splinters, Odin's and XP) were the best bang for your buck.