Cathy and I used the Mayday/Triplanetary vector system in a couple of games at Archon in 2002 or 2003 (I remember Kevin and Dan studiously ignoring us)(we didn't take it personally). This was before the new movement rules used in SAE were introduced. And we used it for our home games. (one of the advantages of having a wife who liked wargaming)
We used the movement points as thrust points and each facing change required a thrust point. Whereas Triplanetary allowed only one thrust point to be expended per turn, we allowed speed to be the max thrust. The mini/counter had to face in the direction of your thrust burn at the end of the burn unless you spent thrust points to rotate to a new heading, which if you think about it, automatically limited the thrust vs time without any ""fiddling".
It worked very well. One interesting side "effect" was you left movement plots all over the map. (Triplanetary uses a marker to plot movements on the grid; Mayday uses counters)-you feel like you're actually plotting TMAs in a CIC.
We noticed a couple of things:
-we seemed to maneuver more than we did using essential Starmada (version Prehistoric)
-In the final analysis the game feel was different, but today using SAE movements would yield very similar results. (Cathy spanked me hard).
That said, there was something very cool about drawing your ships' movements while watching your opponent's target tracks firm up.
For those unfortunate enough not have played these GDW games, a short expo on Triplanetary can be found here:
http://www.kentaurus.com/triplan.htm
Cathy loved playing Triplanetary, especially the race scenario.