From a PQD perspective, none of us are vets - it's a concept that's still relatively new in the grand scheme of things
I would buy up to F/J if it makes sense for you personally. As an example (that turned out not to be needed when my wife and I both got business travel added)...I bought up to F on MSY-EWR. In the end, I would have cleared an RPU (and probably almost CPU), but at the time, that was the difference in getting my wife over the PQM and PQD hurdle for 1K, as well as getting me above 125k PQM (for the extra RPUs). For <$150 on an early morning flight, on a Monday, after partying all night Sunday (wedding that night), it was an easy decision.
In this case, YMMV as always. Since most of my travel is leisure planned in advance, I have a good idea of what I need to do to hit the milestones. The most 'extreme' case is when I bought my wife full-fare F on an EWR-ORD flight on a 3-class 763 to hit 1K a couple years back. It was worth it